{"title":"Engines","description":"\u003cp\u003eHPA engines and pneumatic drive systems for converting or upgrading airsoft rifles.\u003c\/p\u003e","products":[{"product_id":"redline-n7-gen2-hpa-unit","title":"Redline N7 GEN-2 HPA Unit","description":"\n\u003ch4\u003eFeatures:\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003eTrue closed bolt, single solenoid HPA cylinder replacement\u003c\/li\u003e\n\u003cli\u003eEasy setup; minimal FCU tuning required\u003c\/li\u003e\n\u003cli\u003eReduced joule creep; closed-bolt hop tuning\u003c\/li\u003e\n\u003cli\u003eFixed dump chamber—no poppet dwell tuning\u003c\/li\u003e\n\u003cli\u003eConvertible to fully mechanical with optional kit\u003c\/li\u003e\n\u003cli\u003eDesigned \u0026amp; manufactured in the USA\u003c\/li\u003e\n\u003c\/ul\u003e\n","brand":"Redline","offers":[{"title":"V2 \/ Mechanical","offer_id":44483142713378,"sku":"RL-N7-GEN2-MIL-V2","price":299.0,"currency_code":"USD","in_stock":true},{"title":"V2 \/ Standard","offer_id":44483142746146,"sku":"RL-N7-GEN2-FCU-V2","price":359.0,"currency_code":"USD","in_stock":true},{"title":"V3 \/ Mechanical","offer_id":44483142778914,"sku":"RL-N7-GEN2-MIL-V3","price":299.0,"currency_code":"USD","in_stock":true},{"title":"V3 \/ Standard","offer_id":44483142811682,"sku":"RL-N7-GEN2-FCU-V3","price":359.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0741\/5355\/8050\/files\/wmremove-transformed_-_2025-11-04T131916.475.jpg?v=1762975935"},{"product_id":"polarstar-fusion-engine-hpa-kit","title":"PolarStar Fusion Engine™ HPA Drop-In Conversion Kit","description":"\u003cp\u003eThe Fusion Engine™ was released in 2011 as the first new HPA system to hit the airsoft market in over two decades — the system that started the HPA revolution and set the benchmark all others are measured against. Winner of \"Best HPA Engine\" the very first year Popular Airsoft added the HPA class to their Players' Choice Awards.\u003c\/p\u003e\n\n\u003cp\u003eThis complete drop-in system replaces the entire AEG gearbox with a full CNC-machined lightweight aluminum chassis. As a dual solenoid, closed bolt system, the poppet valve (firing air) and nozzle (feeding) are independently adjustable, giving you full control over loading time and air volume. PolarStar Filter Fitting included.\u003c\/p\u003e\n\n\u003ch4\u003eWhy Closed Bolt?\u003c\/h4\u003e\n\u003cp\u003eTrue closed bolt operation makes high accuracy easier to achieve since hop-up configuration is less critical than on open bolt systems. The trigger micro-switch is custom fit to the frame, delivering a distinct break, hard stop, and short reset for the best trigger feel of any system PolarStar produces.\u003c\/p\u003e\n\n\u003ch4\u003eGel Ball Compatible\u003c\/h4\u003e\n\u003cp\u003eFusion Engine conversion kits can be configured for gel ball systems. Contact us for details.\u003c\/p\u003e\n\n\u003ch4\u003ePerformance\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eVelocity:\u003c\/strong\u003e 550fps w\/ .20g @ 120psi — 6 nozzles available to shift velocity range up or down in large increments\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eROF:\u003c\/strong\u003e 30rps+ in most standard configurations\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAir Efficiency:\u003c\/strong\u003e 400+ shots from 13\/3000 @ 1.5J w\/ .28g (can be more than doubled with fine tuning)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOperating Pressure:\u003c\/strong\u003e Widest adjustment range of any PolarStar system\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"PolarStar","offers":[{"title":"V2 GEN3, M4\/M16","offer_id":45868775014434,"sku":"10000434","price":505.0,"currency_code":"USD","in_stock":true},{"title":"V2 GEN3, M4\/M16 – Red LFP\/Red NZ","offer_id":45868775047202,"sku":"10000707","price":505.0,"currency_code":"USD","in_stock":true},{"title":"M249","offer_id":45868775079970,"sku":"10000994","price":510.0,"currency_code":"USD","in_stock":true},{"title":"M240","offer_id":45868775112738,"sku":"10000995","price":510.0,"currency_code":"USD","in_stock":true},{"title":"M60 (A\u0026K)","offer_id":45868775145506,"sku":"10000996","price":515.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0741\/5355\/8050\/files\/ChatGPT_Image_Jun_19_2026_10_25_48_PM_5.png?v=1782930914"},{"product_id":"polarstar-kythera-sa-kit","title":"PolarStar Kythera SA™ Drop-In Conversion Kit","description":"\u003cp\u003eThe Kythera SA™ is PolarStar's most eagerly anticipated product in over a decade — and a radical departure from everything that came before it. The Kythera uses \u003cstrong\u003eno battery, no FCU, and no electronics whatsoever\u003c\/strong\u003e. It is completely mechanical, completely waterproof, and completely unlike anything else on the market. PolarStar Filter Fitting included.\u003c\/p\u003e\n\n\u003cp\u003eNamed after the Antikythera Mechanism — a 2nd-century B.C. astronomical computer so advanced that scientists studied it for decades to understand its purpose — the Kythera valve mechanism is similarly intelligent: few parts, easy to maintain, yet incorporating design principles found nowhere else in airsoft.\u003c\/p\u003e\n\n\u003ch4\u003eWhat Makes It Unique\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eRealistic Trigger:\u003c\/strong\u003e Hardened alloy steel sears catch and release a stainless steel spool valve exactly as a real single-action firearm trigger operates. Distinct break, distinct reset. Adjustable for weight, length of pull, and over travel.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eComplete Shot Cycle on Pull:\u003c\/strong\u003e Delivers proven closed bolt performance mechanically. No trigger release required before the next round chambers. Ready to fire again before the trigger fully resets.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMaximum Efficiency:\u003c\/strong\u003e No pilot valve — 100% of air goes through the nozzle. Consistent valve release every shot regardless of trigger input.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUniversal Charging Cord:\u003c\/strong\u003e Steel cocking cord routes through the grip or attaches to the charging handle for field access if the system stalls (typically only if run completely out of air).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eEasy Installation:\u003c\/strong\u003e Installs as a single assembly into a standard gearbox. No gearbox modification typically required.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch4\u003eGel Ball Compatible\u003c\/h4\u003e\n\u003cp\u003eKythera SA kits can be configured for gel ball use (7–8mm projectiles). Contact us for details.\u003c\/p\u003e\n\n\u003ch4\u003ePerformance\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eVelocity:\u003c\/strong\u003e 270–500fps w\/ .20g (6.05×380mm barrel) across 60–180psi operating range\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eROF:\u003c\/strong\u003e 30rps in most standard configurations\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOperating Pressure Range:\u003c\/strong\u003e 60–180psi — one system covers CQB to DMR by adjusting input pressure\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdjustable:\u003c\/strong\u003e Nozzle dwell, return speed, trigger weight, length of pull, over travel\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"PolarStar","offers":[{"title":"Semi-Auto, V2, M4\/M16","offer_id":45868775178274,"sku":"10000774","price":288.0,"currency_code":"USD","in_stock":true},{"title":"Semi-Auto, V3, AK","offer_id":45868775211042,"sku":"10001002","price":288.0,"currency_code":"USD","in_stock":true},{"title":"Semi-Auto, V2.5, JG SR-25","offer_id":45868775243810,"sku":"10001003","price":303.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0741\/5355\/8050\/files\/ChatGPT_Image_Jun_19_2026_10_25_47_PM_4.png?v=1782930913"},{"product_id":"polarstar-f2-hpa-kit","title":"PolarStar F2™ HPA Conversion Kit","description":"\u003cp\u003eWinner of \"Best HPA Engine\" in the 9th Airsoft Players' Choice Awards, the F2™ delivers the same legendary dual solenoid performance as the Fusion Engine™ in a more compact, efficient, and flexible package. Independently adjustable nozzle and poppet valve give you unparalleled control over loading time and air volume — plus the ability to switch between true closed bolt and \"AEG\" firing modes. PolarStar Filter Fitting included.\u003c\/p\u003e\n\n\u003cp\u003eThe F2™ features a new one-piece lightweight poppet valve that operates at lower pressures and uses less air volume than the Fusion Engine™ poppet, optimizing efficiency. Its spring-biased forward nozzle provides consistent loading force regardless of operating pressure.\u003c\/p\u003e\n\n\u003ch4\u003eGel Ball Compatible\u003c\/h4\u003e\n\u003cp\u003eF2 kits can be configured for gel ball systems. Contact us for details.\u003c\/p\u003e\n\n\u003ch4\u003ePerformance\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eVelocity:\u003c\/strong\u003e Up to 480fps w\/ .20g @ 145psi — full range (below 280fps to 480fps) achievable with a single nozzle just by adjusting pressure\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eROF:\u003c\/strong\u003e 30rps in most standard configurations\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAir Efficiency:\u003c\/strong\u003e 1000+ shots from 13\/3000 @ 1.5J w\/ .28g\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOperating Pressure:\u003c\/strong\u003e 45–145psi\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"PolarStar","offers":[{"title":"V2, M4\/M16","offer_id":45868775276578,"sku":"10000258","price":440.0,"currency_code":"USD","in_stock":true},{"title":"V3, AK","offer_id":45868775309346,"sku":"10000569","price":443.0,"currency_code":"USD","in_stock":true},{"title":"M249","offer_id":45868775342114,"sku":"10000574","price":441.0,"currency_code":"USD","in_stock":true},{"title":"Ares EFCS \/ APS eSE","offer_id":45868775374882,"sku":"10000337","price":447.25,"currency_code":"USD","in_stock":true},{"title":"Ares M4","offer_id":45868775407650,"sku":"10000580","price":448.75,"currency_code":"USD","in_stock":true},{"title":"VFC HK417","offer_id":45868775440418,"sku":"10000399","price":455.75,"currency_code":"USD","in_stock":true},{"title":"M60","offer_id":45868775473186,"sku":"10001316","price":438.0,"currency_code":"USD","in_stock":true},{"title":"KAC LMG","offer_id":45868775505954,"sku":"10000806","price":443.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0741\/5355\/8050\/files\/ChatGPT_Image_Jun_19_2026_10_25_47_PM_2.png?v=1782930913"},{"product_id":"polarstar-f2-offset-hpa-kit","title":"PolarStar F2™ Offset HPA Conversion Kit","description":"\u003cp\u003eThe first true closed bolt offset HPA conversion kit on the market. The F2™ Offset shares the same rear cylinder, poppet valve, and internals as the standard F2™, with a redesigned front cylinder that accommodates offset nozzle configurations for rifles where a center-line nozzle won't work. PolarStar Filter Fitting included.\u003c\/p\u003e\n\n\u003cp\u003eIts front cylinder features dual pin tracks accepting nozzle tips offset to either the top or bottom — broader compatibility without additional components. The two-piece offset nozzle uses a stainless steel support pin to stabilize the longer nozzle and prevent vertical movement, ensuring consistent BB seating and higher accuracy.\u003c\/p\u003e\n\n\u003cp\u003eSame dual solenoid design as the F2™: independently adjustable nozzle and poppet valve, true closed bolt or \"AEG\" firing mode, one-piece lightweight poppet valve, spring-biased forward nozzle, and the full 45–145psi operating pressure range.\u003c\/p\u003e\n\n\u003ch4\u003ePerformance\u003c\/h4\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eVelocity:\u003c\/strong\u003e Up to 480fps w\/ .20g @ 145psi\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eROF:\u003c\/strong\u003e 30rps in most standard configurations\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAir Efficiency:\u003c\/strong\u003e 1000+ shots from 13\/3000 @ 1.5J w\/ .28g\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOperating Pressure:\u003c\/strong\u003e 45–145psi\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"PolarStar","offers":[{"title":"M14, TM","offer_id":45868775538722,"sku":"10000740","price":487.0,"currency_code":"USD","in_stock":true},{"title":"M14, CYMA","offer_id":45868775571490,"sku":"10000741","price":487.0,"currency_code":"USD","in_stock":true},{"title":"M14, G\u0026G","offer_id":45868775604258,"sku":"10000742","price":487.0,"currency_code":"USD","in_stock":true},{"title":"SVD, CYMA","offer_id":45868775637026,"sku":"10000306","price":487.0,"currency_code":"USD","in_stock":true},{"title":"SVD, Real Sword","offer_id":45868775669794,"sku":"10000743","price":495.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0741\/5355\/8050\/files\/F2OS-M14-GG-1.jpg?v=1782930912"},{"product_id":"polarstar-jack-hpa-kit","title":"PolarStar JACK™ HPA Conversion Kit","description":"\u003cp\u003eCode name \"Simple Jack.\" The JACK™ was designed to answer demand for an affordable, high-performance HPA conversion for AEGs — a drop-in cylinder replacement universally compatible with a wide range of gearbox versions that have center-line nozzles. 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