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PolarStar JACK M4/M16 Gearbox HPA Electronic Pneumatic Conversion Kit

SKU: PS-SJV2-M4 PolarStarOut of stock Map ProtectedPrice is map protected. Coupon(s) may not be applied to this item.

  • PolarStar's affordable and efficient HPA conversion for AEG's
  • Easy switch out nozzle makes kit universally with a wide range of gearboxes
  • A single moving part makes the rifle very reliable and easy to maintain
  • Able to adjust your muzzle velocity substantially from 250 to 500 FPS
  • Max velocity potential varies depending on barrel length and tightness of the bore
  • Includes an on-board FCU (Fire Control Unit)
  • Adjust cyclic rate, fire modes and poppet dwell
  • Stabilizes the BB in the hop up before firing
  • Improves hop up performance with a wide range of stock and aftermarket options
  • Replaces original gearbox pars with a programmable pneumatic system for enhanced reliability


In the Box

1X Jack Engine



Brand Polarstar
Nozzle Type M4/M16
Propellant HPA
Material Aluminum Alloy
Legnth 4" Inches

California Proposition 65 Warning: Cancer and Reproductive Harm -

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