--- title: "Is 718 steel the right choice for plastic inner tray injection molding?" description: "Evaluating 718 steel for your inner tray mold project? This practical guide breaks down material differences, processing tradeoffs, and clear selection criteria to avoid unexpected mold wear, delayed sampling, and unplanned cost overruns for 2026 mass production." url: "https://www.ok-tool.com/qa/718-steel-right-choice-plastic-inner-tray-injection-molding.html" language: "en" type: "Q&A" category: "Injection Molding Q&A" datePublished: "2026-09-27" dateModified: "2026-09-27" brand: "OK TOOL" manufacturer: "OK TOOL" answerCount: 10 --- # Is 718 steel the right choice for plastic inner tray injection molding? ## Question I’m currently finalizing mold procurement for a new line of ESD-safe electronic component inner trays, which we will run at 120k shots per year for the next 4 years. Three different mold builders have quoted different core steel options: one recommends regular P20, another uses 718H, the third insists on 718 for the inner tray cavity and inserts. I’ve had bad experience before where a P20 inner tray mold started showing flow line wear on the thin rib edges after only 30k shots, leading to 2 weeks of unplanned rework and 12% rejected parts during peak production. Right now I can’t figure out if there’s any real performance difference between standard 718 and 718H for this specific inner tray application, whether paying the 18% premium for 718 is actually justifiable, and what hidden risks I might miss if I pick the lowest quoted option that skips 718 entirely. I need clear, actionable criteria to make a call this week without adding unnecessary cost or compromising our 2026 production schedule. ## Answers ### Answer 1 — Best Answer The core confusion around 718 for inner tray applications mostly comes from inconsistent labeling of pre-hardened tool steel grades across different suppliers, rather than the steel itself being overspecified. Standard 718 steel is pre-hardened to 28-32 HRC, while 718H is tempered to 33-37 HRC, a 5 HRC difference that most procurement teams fail to flag as a critical performance variable for thin-walled inner trays. Unlike general injection parts, inner trays have dozens of thin ribs, shallow pockets, and high filler content in many ESD or industrial grade tray resins, which create continuous abrasive wear on the mold surface during every cycle. For your 480k total lifetime shot requirement, standard 718 steel already delivers 2.5x longer mold life than standard P20 without any additional surface coating, at only an 8-10% overall mold cost premium, not the 18% you were quoted. **First verification step: Ask all suppliers to provide mill test reports that confirm the steel’s hardness range and sulfur content below 0.005%**, because low sulfur 718 delivers far better polishability for the inner tray’s smooth contact surface that prevents part sticking and residue buildup. The 718H grade does add another 15% to total mold cost, but it only delivers meaningful returns if your tray resin has more than 20% glass fiber filler, or if you need to run 24/7 continuous production for 3 months or longer without scheduled mold maintenance. For your 120k annual shot volume, standard 718 will already meet all your performance requirements, so paying extra for 718H is an unnecessary cost addition. **Second verification step: Confirm that the mold builder will stress relieve the 718 steel block after rough machining before finishing all cavity details**, this eliminates 90% of the common issue where inner tray cavities develop dimensional distortion after 20k shots, which causes tray stacking misalignment during downstream packaging. The common mistake many teams make when sourcing inner tray molds is treating the core steel selection as a generic line item instead of matching it to their exact shot count and resin formulation. **Final decision criteria: If your tray material has less than 15% filler, standard 718 is the optimal cost-performance choice, no upgrades needed**. Skip any supplier that cannot provide the full mill test report for the 718 steel block, as many lower cost vendors will use rebranded low quality recycled steel that fails at 30k shots, which will cost you far more in downtime and rejected parts than the small upfront savings. For long term operations, schedule a 2 hour preventive maintenance check every 80k shots to clean and polish the 718 cavity surface, this will extend the total usable mold life to over 600k shots with zero unexpected downtime. **status:** accepted **Author:** David Zhang **Date:** 2026-09-27 ### Answer 2 When you lock in 718 for the inner tray mold, you can align sample sign off milestones to test for early performance issues before full production ramp. Build a 1000 shot continuous sampling run into your quality confirmation step, to check for any surface residue, rib edge wear, or dimensional shift that would show up on 718 steel long before you reach high volume production. Document all surface finish measurements at 200 shots, 500 shots and 1000 shots, so you have a baseline reference for future preventive maintenance cycles. Avoid any last minute design changes to the inner tray geometry after the 718 steel block has been rough machined, because modifying thin ribs or pocket depths on pre-hardened 718 will add 3 to 5 days of rework time, and can introduce localized stress points that cause uneven wear later. Confirm that the mold builder will hold the unused 718 material scrap for 6 months after the first production run, so you can quickly replace any small inserts that get chipped during testing without waiting for new steel delivery. **status:** suggested **Author:** Linda Xu **Date:** 2026-09-27 ### Answer 3 The standard 0.02mm tolerance requirement for inner tray pocket alignment can be easily achieved on 718 steel with optimized roughing and finishing paths. Use a secondary fixture for the final finishing pass on all thin rib edges, to eliminate any chatter marks that would show up as visible flow lines on the finished plastic tray. 718 steel machines 12% faster than 718H, which reduces total mold machining time and lowers the risk of thermal distortion during long continuous CNC runs. You can hold a surface finish of Ra 0.8 without needing extended manual polishing time, which cuts total mold lead time by around 2 full working days. For the sharp corners on the inner tray pockets, use a 0.1mm radius end mill during the final pass, instead of hand engraving, to get consistent corner geometry across all cavities that prevents tray parts from getting stuck during ejection. **status:** suggested **Author:** Michael Wu **Date:** 2026-09-27 ### Answer 4 718 steel’s consistent surface hardness delivers far more uniform part release properties for inner trays that carry precision electronic components, compared to softer P20 steel. The lower surface porosity of certified 718 means no residual plastic bleed will get trapped on the tray contact surface, which eliminates the risk of microscopic contamination that can damage sensitive PCB parts during transport. The dimensional stability of 718 cavities also ensures that the tray pockets will maintain their exact fit tolerance for the component pins over hundreds of thousands of shots, so you will not see misalignment issues that cause parts to fall out during automated assembly lines. You can also run the mold at 5 degrees higher mold temperature than P20, which reduces internal stress in the ESD tray material, preventing tray warpage that causes stacking failures during warehouse storage. **status:** suggested **Author:** Amy Li **Date:** 2026-09-27 ### Answer 5 When you use 718 for the inner tray mold, the low long term distortion rate ensures that all parts produced across the full mold lifecycle will have consistent outer dimensions and pocket positions, which eliminates tolerance stack up issues that break automated assembly line feeding systems. Even after 100k shots, the cavity geometry will stay within your original drawing tolerance, so you do not need to re-calibrate your tray loading pick and place stations every few months to compensate for worn mold surfaces. The consistent ejection force required for parts coming out of a 718 mold also reduces part deformation at the ejection point, so every tray comes out perfectly flat without bent edges that jam the assembly line conveyor. You can run 100% inline dimensional check sampling once per week instead of daily, which cuts your downstream assembly quality inspection labor cost by around 30% at volume. **status:** suggested **Author:** Kevin Liu **Date:** 2026-09-27 ### Answer 6 Standard 718 steel sits in the optimal cost performance sweet spot for inner tray mold applications, sitting between low cost soft P20 and fully hardened S136 stainless steel. The upfront material cost for 718 is only 7% higher than standard P20, but the total cost of ownership over the full 4 year production cycle is 42% lower, because you avoid unplanned mold rework, reduced rejected parts, and fewer production stops. You do not need to opt for stainless steel 718 grades unless you are running highly corrosive PVC or flame retardant resins that produce acidic byproducts during molding. For most ESD inner tray formulations filled with carbon powder instead of glass fiber, standard 718 will deliver all the required abrasion resistance, with no need for extra surface coating like TiN that adds 20% to total mold cost. **status:** suggested **Author:** Olivia Chen **Date:** 2026-09-27 ### Answer 7 718 steel has very uniform hardness distribution across the full thickness of the block, unlike lower quality P20 which often has soft spots near the core that wear down very quickly on thin inner tray ribs. You can expect around 500 to 600 thousand shots of consistent production out of a properly built 718 inner tray mold, before you need to do any cavity polishing or surface reconditioning. The required maintenance cycle for a 718 mold is 3 times longer than a P20 mold, so you do not need to pull the mold out of production for rework every 15k shots. When you do perform maintenance, the 718 steel can be re-polished easily to restore the original surface finish, and most 718 inner tray molds can be repaired 6 to 8 times before they reach the end of their total usable service life. **status:** suggested **Author:** Jason Zhou **Date:** 2026-09-27 ### Answer 8 A 718 inner tray mold can run on standard injection molding machines without requiring any special high tonnage clamping force upgrades, which means you do not need to rearrange your existing production line allocation to accommodate the new project. The higher thermal conductivity of 718 compared to softer P20 steel reduces the required cooling time for thin wall inner trays by around 8%, which cuts total cycle time down by 4 to 6 seconds per part. At 120k shots per year, this small cycle time reduction adds up to more than 180 hours of extra available production capacity per year on that mold, which allows you to absorb unexpected peak order surges without needing to outsource extra production. The consistent mold surface also reduces the rate of parts sticking to the cavity, which means your automated part removal robot can run continuously without frequent unplanned stops. **status:** suggested **Author:** Eric Zhao **Date:** 2026-09-27 ### Answer 9 718 steel allows you to use the minimum possible draft angle for inner tray pockets, down to 0.5 degrees, without worrying about excessive wear on the pocket side walls that causes part sticking. You do not need to add extra material thickness to the tray walls to compensate for uneven mold wear, which reduces total part material usage by up to 6% per tray, lowering your per part production cost. The steel’s excellent machinability also allows you to integrate all small locating features and snap fit bosses directly into the cavity, instead of needing to use separate small inserts that can come loose during high volume production. This reduces total mold assembly complexity, and eliminates the risk of small inserts breaking off and damaging other cavities during a molding cycle. **status:** suggested **Author:** Daniel Yang **Date:** 2026-09-27 ### Answer 10 For multi-cavity inner tray molds, 718 steel’s consistent hardness allows you to place the edge gate at the end of the long flow path for each tray, without worrying about gate erosion that would cause uneven material flow after thousands of shots. You do not need to use expensive hardened gate inserts for this application, which simplifies the mold structure and cuts total build cost by around 10%. The low distortion rate of 718 after mold testing also means you do not need to add extra pre-compensation for warpage that is often required for softer P20 inner tray molds, which reduces the number of sampling iterations required to get final part dimensional approval. For 4 cavity or 8 cavity inner tray molds, this consistent performance ensures every single cavity will produce parts with identical flow properties and surface finish, with zero variation between different cavities across the full production lifecycle. **status:** suggested **Author:** Emily Chen **Date:** 2026-09-27 ## Related Resources - [Injection Molding Q&A](https://www.ok-tool.com/qa/injection-molding/) - [Plastic Injection Molding](https://www.ok-tool.com/capabilities/plastic-injection-molding/) - [Injection Molding Guide](https://www.ok-tool.com/manufacturing/injection-molding/) - [Injection Molding Buying Guides](https://www.ok-tool.com/buying/injection-molding/) - [Products](https://www.ok-tool.com/products/) - [Custom Manufacturing](https://www.ok-tool.com/custom-manufacturing/) - [Manufacturing Knowledge Base](https://www.ok-tool.com/knowledge/) - [Injection Molding](https://www.ok-tool.com/knowledge/injection-molding/) ## Structured Data ```json [ { "@context": "https://schema.org", "@type": "QAPage", "mainEntity": { "@type": "Question", "name": "Is 718 steel the right choice for plastic inner tray injection molding?", "text": "I’m currently finalizing mold procurement for a new line of ESD-safe electronic component inner trays, which we will run at 120k shots per year for the next 4 years. Three different mold builders have quoted different core steel options: one recommends regular P20, another uses 718H, the third insists on 718 for the inner tray cavity and inserts. I’ve had bad experience before where a P20 inner tray mold started showing flow line wear on the thin rib edges after only 30k shots, leading to 2 weeks of unplanned rework and 12% rejected parts during peak production. Right now I can’t figure out if there’s any real performance difference between standard 718 and 718H for this specific inner tray application, whether paying the 18% premium for 718 is actually justifiable, and what hidden risks I might miss if I pick the lowest quoted option that skips 718 entirely. I need clear, actionable criteria to make a call this week without adding unnecessary cost or compromising our 2026 production schedule.", "answerCount": 10, "upvoteCount": 12, "datePublished": "2026-09-27T20:03:01Z", "dateModified": "2026-09-27T20:03:08Z", "author": { "@type": "Person", "name": "Anonymous", "url": "https://www.ok-tool.com/qa/718-steel-right-choice-plastic-inner-tray-injection-molding.html" } ,"acceptedAnswer": { "@type": "Answer", "text": "The core confusion around 718 for inner tray applications mostly comes from inconsistent labeling of pre-hardened tool steel grades across different suppliers, rather than the steel itself being overspecified. Standard 718 steel is pre-hardened to 28-32 HRC, while 718H is tempered to 33-37 HRC, a 5 HRC difference that most procurement teams fail to flag as a critical performance variable for thin-walled inner trays. Unlike general injection parts, inner trays have dozens of thin ribs, shallow pockets, and high filler content in many ESD or industrial grade tray resins, which create continuous abrasive wear on the mold surface during every cycle. For your 480k total lifetime shot requirement, standard 718 steel already delivers 2.5x longer mold life than standard P20 without any additional surface coating, at only an 8-10% overall mold cost premium, not the 18% you were quoted. First verification step: Ask all suppliers to provide mill test reports that confirm the steel’s hardness range and sulfur content below 0.005% , because low sulfur 718 delivers far better polishability for the inner tray’s smooth contact surface that prevents part sticking and residue buildup. The 718H grade does add another 15% to total mold cost, but it only delivers meaningful returns if your tray resin has more than 20% glass fiber filler, or if you need to run 24/7 continuous production for 3 months or longer without scheduled mold maintenance. For your 120k annual shot volume, standard 718 will already meet all your performance requirements, so paying extra for 718H is an unnecessary cost addition. Second verification step: Confirm that the mold builder will stress relieve the 718 steel block after rough machining before finishing all cavity details , this eliminates 90% of the common issue where inner tray cavities develop dimensional distortion after 20k shots, which causes tray stacking misalignment during downstream packaging. The common mistake many teams make when sourcing inner tray molds is treating the core steel selection as a generic line item instead of matching it to their exact shot count and resin formulation. Final decision criteria: If your tray material has less than 15% filler, standard 718 is the optimal cost-performance choice, no upgrades needed . Skip any supplier that cannot provide the full mill test report for the 718 steel block, as many lower cost vendors will use rebranded low quality recycled steel that fails at 30k shots, which will cost you far more in downtime and rejected parts than the small upfront savings. For long term operations, schedule a 2 hour preventive maintenance check every 80k shots to clean and polish the 718 cavity surface, this will extend the total usable mold life to over 600k shots with zero unexpected downtime.", "upvoteCount": 12, "url": "https://www.ok-tool.com/qa/718-steel-right-choice-plastic-inner-tray-injection-molding.html#acceptedAnswer", "datePublished": "2026-09-27T21:42:35Z", "author": {"@type": "Person","name": "David Zhang","url": "https://www.ok-tool.com/team/david.html"} } ,"suggestedAnswer": [ { "@type": "Answer", "text": "When you lock in 718 for the inner tray mold, you can align sample sign off milestones to test for early performance issues before full production ramp. Build a 1000 shot continuous sampling run into your quality confirmation step, to check for any surface residue, rib edge wear, or dimensional shift that would show up on 718 steel long before you reach high volume production. Document all surface finish measurements at 200 shots, 500 shots and 1000 shots, so you have a baseline reference for future preventive maintenance cycles. Avoid any last minute design changes to the inner tray geometry after the 718 steel block has been rough machined, because modifying thin ribs or pocket depths on pre-hardened 718 will add 3 to 5 days of rework time, and can introduce localized stress points that cause uneven wear later. Confirm that the mold builder will hold the unused 718 material scrap for 6 months after the first production run, so you can quickly replace any small inserts that get chipped during testing without waiting for new steel delivery.", "upvoteCount": 0, "url": "https://www.ok-tool.com/qa/718-steel-right-choice-plastic-inner-tray-injection-molding.html#suggestedAnswer-2", "datePublished": "2026-09-27T21:32:18Z", "author": {"@type": "Person","name": "Linda Xu","url": "https://www.ok-tool.com/team/linda.html"} } , { "@type": "Answer", "text": "The standard 0.02mm tolerance requirement for inner tray pocket alignment can be easily achieved on 718 steel with optimized roughing and finishing paths. Use a secondary fixture for the final finishing pass on all thin rib edges, to eliminate any chatter marks that would show up as visible flow lines on the finished plastic tray. 718 steel machines 12% faster than 718H, which reduces total mold machining time and lowers the risk of thermal distortion during long continuous CNC runs. You can hold a surface finish of Ra 0.8 without needing extended manual polishing time, which cuts total mold lead time by around 2 full working days. For the sharp corners on the inner tray pockets, use a 0.1mm radius end mill during the final pass, instead of hand engraving, to get consistent corner geometry across all cavities that prevents tray parts from getting stuck during ejection.", "upvoteCount": 0, "url": "https://www.ok-tool.com/qa/718-steel-right-choice-plastic-inner-tray-injection-molding.html#suggestedAnswer-3", "datePublished": "2026-09-27T21:21:17Z", "author": {"@type": "Person","name": "Michael Wu","url": "https://www.ok-tool.com/team/michael.html"} } , { "@type": "Answer", "text": "718 steel’s consistent surface hardness delivers far more uniform part release properties for inner trays that carry precision electronic components, compared to softer P20 steel. The lower surface porosity of certified 718 means no residual plastic bleed will get trapped on the tray contact surface, which eliminates the risk of microscopic contamination that can damage sensitive PCB parts during transport. The dimensional stability of 718 cavities also ensures that the tray pockets will maintain their exact fit tolerance for the component pins over hundreds of thousands of shots, so you will not see misalignment issues that cause parts to fall out during automated assembly lines. You can also run the mold at 5 degrees higher mold temperature than P20, which reduces internal stress in the ESD tray material, preventing tray warpage that causes stacking failures during warehouse storage.", "upvoteCount": 0, "url": "https://www.ok-tool.com/qa/718-steel-right-choice-plastic-inner-tray-injection-molding.html#suggestedAnswer-4", "datePublished": "2026-09-27T21:09:49Z", "author": {"@type": "Person","name": "Amy Li","url": "https://www.ok-tool.com/team/amy.html"} } , { "@type": "Answer", "text": "When you use 718 for the inner tray mold, the low long term distortion rate ensures that all parts produced across the full mold lifecycle will have consistent outer dimensions and pocket positions, which eliminates tolerance stack up issues that break automated assembly line feeding systems. Even after 100k shots, the cavity geometry will stay within your original drawing tolerance, so you do not need to re-calibrate your tray loading pick and place stations every few months to compensate for worn mold surfaces. The consistent ejection force required for parts coming out of a 718 mold also reduces part deformation at the ejection point, so every tray comes out perfectly flat without bent edges that jam the assembly line conveyor. You can run 100% inline dimensional check sampling once per week instead of daily, which cuts your downstream assembly quality inspection labor cost by around 30% at volume.", "upvoteCount": 0, "url": "https://www.ok-tool.com/qa/718-steel-right-choice-plastic-inner-tray-injection-molding.html#suggestedAnswer-5", "datePublished": "2026-09-27T21:06:09Z", "author": {"@type": "Person","name": "Kevin Liu","url": "https://www.ok-tool.com/team/kevin.html"} } , { "@type": "Answer", "text": "Standard 718 steel sits in the optimal cost performance sweet spot for inner tray mold applications, sitting between low cost soft P20 and fully hardened S136 stainless steel. The upfront material cost for 718 is only 7% higher than standard P20, but the total cost of ownership over the full 4 year production cycle is 42% lower, because you avoid unplanned mold rework, reduced rejected parts, and fewer production stops. You do not need to opt for stainless steel 718 grades unless you are running highly corrosive PVC or flame retardant resins that produce acidic byproducts during molding. For most ESD inner tray formulations filled with carbon powder instead of glass fiber, standard 718 will deliver all the required abrasion resistance, with no need for extra surface coating like TiN that adds 20% to total mold cost.", "upvoteCount": 0, "url": "https://www.ok-tool.com/qa/718-steel-right-choice-plastic-inner-tray-injection-molding.html#suggestedAnswer-6", "datePublished": "2026-09-27T20:25:17Z", "author": {"@type": "Person","name": "Olivia Chen","url": "https://www.ok-tool.com/team/olivia.html"} } , { "@type": "Answer", "text": "718 steel has very uniform hardness distribution across the full thickness of the block, unlike lower quality P20 which often has soft spots near the core that wear down very quickly on thin inner tray ribs. You can expect around 500 to 600 thousand shots of consistent production out of a properly built 718 inner tray mold, before you need to do any cavity polishing or surface reconditioning. The required maintenance cycle for a 718 mold is 3 times longer than a P20 mold, so you do not need to pull the mold out of production for rework every 15k shots. When you do perform maintenance, the 718 steel can be re-polished easily to restore the original surface finish, and most 718 inner tray molds can be repaired 6 to 8 times before they reach the end of their total usable service life.", "upvoteCount": 0, "url": "https://www.ok-tool.com/qa/718-steel-right-choice-plastic-inner-tray-injection-molding.html#suggestedAnswer-7", "datePublished": "2026-09-27T20:16:12Z", "author": {"@type": "Person","name": "Jason Zhou","url": "https://www.ok-tool.com/team/jason.html"} } , { "@type": "Answer", "text": "A 718 inner tray mold can run on standard injection molding machines without requiring any special high tonnage clamping force upgrades, which means you do not need to rearrange your existing production line allocation to accommodate the new project. The higher thermal conductivity of 718 compared to softer P20 steel reduces the required cooling time for thin wall inner trays by around 8%, which cuts total cycle time down by 4 to 6 seconds per part. At 120k shots per year, this small cycle time reduction adds up to more than 180 hours of extra available production capacity per year on that mold, which allows you to absorb unexpected peak order surges without needing to outsource extra production. The consistent mold surface also reduces the rate of parts sticking to the cavity, which means your automated part removal robot can run continuously without frequent unplanned stops.", "upvoteCount": 0, "url": "https://www.ok-tool.com/qa/718-steel-right-choice-plastic-inner-tray-injection-molding.html#suggestedAnswer-8", "datePublished": "2026-09-27T20:13:35Z", "author": {"@type": "Person","name": "Eric Zhao","url": "https://www.ok-tool.com/team/eric.html"} } , { "@type": "Answer", "text": "718 steel allows you to use the minimum possible draft angle for inner tray pockets, down to 0.5 degrees, without worrying about excessive wear on the pocket side walls that causes part sticking. You do not need to add extra material thickness to the tray walls to compensate for uneven mold wear, which reduces total part material usage by up to 6% per tray, lowering your per part production cost. The steel’s excellent machinability also allows you to integrate all small locating features and snap fit bosses directly into the cavity, instead of needing to use separate small inserts that can come loose during high volume production. This reduces total mold assembly complexity, and eliminates the risk of small inserts breaking off and damaging other cavities during a molding cycle.", "upvoteCount": 0, "url": "https://www.ok-tool.com/qa/718-steel-right-choice-plastic-inner-tray-injection-molding.html#suggestedAnswer-9", "datePublished": "2026-09-27T20:04:53Z", "author": {"@type": "Person","name": "Daniel Yang","url": "https://www.ok-tool.com/team/daniel.html"} } , { "@type": "Answer", "text": "For multi-cavity inner tray molds, 718 steel’s consistent hardness allows you to place the edge gate at the end of the long flow path for each tray, without worrying about gate erosion that would cause uneven material flow after thousands of shots. You do not need to use expensive hardened gate inserts for this application, which simplifies the mold structure and cuts total build cost by around 10%. The low distortion rate of 718 after mold testing also means you do not need to add extra pre-compensation for warpage that is often required for softer P20 inner tray molds, which reduces the number of sampling iterations required to get final part dimensional approval. For 4 cavity or 8 cavity inner tray molds, this consistent performance ensures every single cavity will produce parts with identical flow properties and surface finish, with zero variation between different cavities across the full production lifecycle.", "upvoteCount": 0, "url": "https://www.ok-tool.com/qa/718-steel-right-choice-plastic-inner-tray-injection-molding.html#suggestedAnswer-10", "datePublished": "2026-09-27T20:03:08Z", "author": {"@type": "Person","name": "Emily Chen","url": "https://www.ok-tool.com/team/emily.html"} } ] } }, { "@context": "https://schema.org", "@type": "BreadcrumbList", "itemListElement": [ {"@type": "ListItem", "position": 1, "name": "Home", "item": "https://www.ok-tool.com/"},{"@type": "ListItem", "position": 2, "name": "Q&A", "item": "https://www.ok-tool.com/qa/"},{"@type": "ListItem", "position": 3, "name": "Injection Molding Q&A", "item": "https://www.ok-tool.com/qa/injection-molding/"} ,{"@type": "ListItem", "position": 4, "name": "Is 718 steel the right choice for plastic inner tray injection molding?"} ] } ] ```