Retro Arms CNC SOPMOD M4 NGRS Gearbox 8mm

Retro Arms CNC gearbox for TM NGRS SOPMOD M4 AEG. 

When it comes to building a reliable high tier NGRS, this gearbox should be your first item in your build. With the stress of recoil, you need to have the strongest gearbox possible. 

• Precision machined from a block of billet EN AW 7075 T651 aluminum
• Durable anodized finish
• Reinforcement in key stress points to counter rapid wear from high performance parts
• Pre-radiused cylinder windows - helps evenly distribute impact force
• Deeper wire channels along base of gearbox

Unlike most other gearbox shells on the market, the Retro Arms CZ gearbox shells are precision CNC machined out of a solid block of billet EN AW 7075 T651 aluminum giving them unmatched durability and resilience. Combined with reinforcement of key stress points and stainless steel connecting bolts, the gearbox shell has undergone extensive stress tests with M160 springs without any signs of wear.