Modify Complete M4-A1/M16 Upgrade Gear Box. (Torque Type/ S120+)

The Ultimate Mid Torque Gearbox set up available on the market today. The Modify Torque Type Gearbox set is encased by the solid Torus Gearbox shell, and loaded with modify's most revolutionary internals for maximum speed and accuracy.
Equipped with S120+ spring set up.

Motor connector ends not included