Polarstar Complete O – Ring and Screw Set for Jack (Not for MP7)

PolarStar Complete O-Ring and Screw Set – JACK (Not for MP7)

The PolarStar Complete O-Ring and Screw Set for JACK is the OEM maintenance kit for the standard PolarStar JACK HPA AEG engine — compatible with all JACK installations except the MP7 variant (which uses different dimensions and has its own separate kit). The JACK is PolarStar’s direct-replacement HPA engine for standard V2 AEG gearbox platforms — dropping into the gearbox shell for a clean AEG-format HPA conversion. The engine contains multiple O-rings at the piston, nozzle, and valve positions, plus screws securing the engine body and internals that can loosen through field use and vibration. This complete kit replaces all engine O-rings and screws in one maintenance pass.

OEM PolarStar maintenance kit for standard JACK engine servicing. Not for MP7 builds — see the separate JACK MP7 kit for those platforms. For standard JACK operators experiencing air leaks, velocity loss, or loose internal screws, this is the correct complete maintenance kit for the standard JACK engine.

• PolarStar Complete O-Ring and Screw Set — JACK
• For standard JACK engine — NOT for MP7 platform builds
• Complete O-rings and screws for full JACK engine service
• Restores air sealing and internal hardware integrity
• Made by PolarStar Airsoft