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Fully CNC machined Duraluminium gearbox shell for all Version 2 type RIFs. 

Retro Arms make arguably the strongest gearbox shells in the world so if you want something basically indestructible, look no further. 
These gearboxes take all standard fittings and come with T10 Torx screws.


Package includes: CNC Gearbox V2 (8mm),  set of screws and QSC spring guide.


Retro Arms made some useful improvements for this latest generation of CNC gearboxes:


  • Spring holders have grooves, so the springs for tappet plate and trigger switch will not jump off.
  • Added groove for safety lever, so it will hold during installation.
  • AOE viewing hole.
  • Holes for bushings/bearings have smaller diameter about -0.02mm (7.98mm) to securely hold most bushings and bearings in place without the need for stud lock.
  • Enlarged wiring channels for use with wiring up to 2.5mm diameter.
  • Added protecting edge for wiring under the motor pinion.
  • Stronger screw threads.
  • Both of the gearbox parts are centered by milled grooves and edges.
  • Added hole for releasing anti-reverse latch.
  • For better durability, there is added material around the cylinder head along with pre-radiused corners.
  • Added groove for anti-reversal latch spring, so it will not jump off.

Retro Arms CNC Gearbox V2 (8mm) – QSC

Out of Stock
  • Installation Notes

    Takes 8mm bushings or bearings. 
    Compatible with the vast majority of V2 RIFs however some modifications to the receiver or gearbox shell may be required in some brands. 
    We don't recommend these for TM MP5s due to the gearboxes slightly non-standard external design. 

    We recommend all surfaces that come in to contact with moving parts be lubricated with Superlube PTFE grease. 
    All screws should be secured using Loctite 266 thread lock or similar upon final assembly. 

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