Rocket Airsoft M120 AEG Spring - Japanese Black Steel

Rocket Airsoft M120 AEG Spring Japanese Black Steel. One of our most popular airsoft upgrade springs! Very high quality steel made spring to get your gun running just below 400 FPS. Fits in all standard gearboxes. This is your standard upgrade spring strength for upgrades. (please note: packaging may be generic or labeled as 'Rocket Airsoft', but is made by SHS OEM) This is a non-linear spring utilizing Japanese made steel spring material. Black color to differentiate spring types.