G&G Top Tech Pneumatic V2 MP5 Gearbox for sale. Getting harder to find these gearboxes and with blowback system intact! Lightly used from previous owner then taken out for hpa build i was told. Factory seal still intact! These are in my opinion one of the best blowback designs without adding stress to your gearbox components. One of my quietest cycling and +/-1 fps builds was achieved using one of these gearboxes while still having the blowback functioning....good times lol