SKU: 99206998798

Polarstar JACK HPA Conversion Kit

Sale price$137.22 Regular price$152.47
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Ships within 48 hours · Estimated delivery Jul 26 - Jul 31

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Description

Polarstar JACK HPA Conversion KitWe can custom anodize your Jack in the colors you want for $100 more. All kits come with a Filter Fitting installed, FCU, Switchboard, Wire Harness and any additional components needed to convert the specific airsoft rifle model for which the kit is configured. The HPA Tank, Air Rig (regulator and line) and Battery needed to operate the system are purchased separately. Code Name "Simple Jack" The JACK was designed to answer the demand for an

We can custom anodize your Jack in the colors you want for $100 more.

Code Name "Simple Jack"

The JACK™ was designed to answer the demand for an affordable, high performance HPA (High Pressure Air) conversion for AEG's. The system is a drop-in cylinder replacement that is universally compatible with a wide range of gearbox versions that have center-line nozzles. PolarStar Filter Fitting now included!

Similar to its sister products, the JACK™ replaces the original gearbox components with a programmable pneumatic system allowing for higher performance and greater reliability over a gear driven system. Although economically priced, the JACK™ still retains the same performance and quality you have come to expect from PolarStar products.

The JACK™ has only one moving part, the nozzle, which acts as its own poppet valve. Similar to the Fusion Engine™ and F2™ poppet, the nozzle is only piloted by the solenoid to open air flow through the poppet with none of the firing air coming from the solenoid itself. This design lets the JACK™ send a higher flow of air down the barrel than systems that only use a solenoid as the firing valve.

Gel Ball Compatible

JACK HPA conversion kits can also be configured for use in gel ball systems.

Please contact us for information on ordering JACK systems for gel ball use.

Velocity: 500fps w/ .20g @ 130psi
The JACK™ allows for easy velocity adjustment by changing input pressure and does not require different nozzles to reach its full velocity range. Using a standard M4 as an example, velocity can be adjusted from below 280fps and up to approximately 500fps with a .20g BB. Velocity can vary per model as longer barrels will increase the maximum velocity while shorter barrels will decrease it. 
ROF: 30rps
The maximum cyclic rate of the JACK™ is affected by several factors such as the operating pressure as well as quality of the magazine and BB's used. However, 30 rounds per second is achievable in most standard configurations.
Air Efficiency: 1000+ shots from 13/3000 @ 1.5J  w/ .28g
Although not a critical requirement during development, JACK™ does boast some highly respectable figures in this category. This is made possible by its intelligently laid out design which minimizes dead volume resulting in better air flow, faster response and less air used per shot.
(Test Configuration: 6.05x375mm Barrel)
Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 99206998798

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Reviewed in the United States on May 22, 2026
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Reviewed in the United States on April 21, 2026
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