Polarstar JACK - HPA Standard FCU Conversion Kit Spring Shotguns Quick Focus Eyepiece

Quick Focus Eyepiece

Tripod ready mounting hole (standard camera screw / camcorder tripods )

Uses UMP magazines - hicap or midcap

ceramic coffee mug

Polarstar JACK - HPA Standard FCU Conversion Kit Spring Shotguns Quick Focus EyepieceThe Polarstar JACK HPA Standard FCU Conversion Kit. This is the full sized FCU version for easy programming. Contains everything you need internally. Works drop in with most M4 AK platforms. G&G, Elite Force, JG, and most are pretty easy to install. Watch some Youtube videos on how to put it in yourself. With the Polarstar JACK engine, all you need to complete your HPA setup is: HPA Air Tank (non SLP tan regulator is okay, Ninja, Valken, FS is good)