This jm gen8 gearbox shells is compatible with for the new verison JinMing J8 M4A1 gel blaster with semi/auto fire modes or the older verions which is only with full auto shooting mode.

Specifications:

Brand: JM.
Material: nylon.
Color: black.
Compatibility: new or old jm j8 gel blaster.
SIze: 20*8*2cm.
Weight: 85g.

Package Contents:

1x jinming gen8 gearbox shell.
1x nylon t-piece.
1x motor holder.
1x spring retainer.