Rocket Airsoft M190 AEG Spring - Japanese Black Steel

Rocket Airsoft M190 AEG Spring Japanese Black Steel. Very high quality steel made spring to get your gun running a very high FPS. Fits in all standard gearboxes. This is your standard upgrade spring strength for upgrades. M190 is not recommended for most builds - buyer beware. This is a non-linear spring utilizing Japanese made steel spring material. Black color to differentiate spring types.