G&G have shared details of their G2/G2H gearboxes:
G2/G2H Gearboxes
Our enhanced G2/G2H complete gearboxes are the perfect solution for anyone looking to elevate their performance on the battlefield. We’ve reinforced the outer shell of the gearbox to prevent cracking under stress, improved compression by adding double o-rings on the cylinder head, and added a quick spring change capability to name a few features. The upgraded gearboxes are easy to drop in the receiver and avoid the complications of assembling any internals. Now available worldwide.Find your local G&G Dealer
G&G
