Bullgear Marui 416 / M4 CNC Recoil Shock Gearbox. 

For 7mm bushings.


Production method: 100% CNC


Material: Aluminum

Bullgear Marui 416 / M4 CNC NGRS Gearbox Shell

  • Please note that this gearbox shell requires modification to work with trigger-replacement MOSFET units and is not compatible with the BTC Spectre at all. 

    Some modification may be required to the screws and shell for smooth operation of the empty mag system and blowback assembly. 

    We recommend FLT 7mm Steel Bushings for this shell.

    Expert-level tech experience recommended.