Elite Force Complete Gearbox w/ CFR Spring

Replacement gearbox for all Elite Force M4 CQB Series AEG Rifles. This high quality Version 2 gearbox comes fully built and ready to drop-in your favorite AEG, and features a high-tension CFR Spring and Micro Switch trigger. The integrated Quick Change Spring System makes it simple and easy to upgrade or replace the spring mechanism within this gearbox. Features: Version 2 Gearbox High Tension CFR Spring Micro Switch Trigger Full Metal Reinforced Tooth Piston Quick Change Spring System Reinforced Tappet Plate