Rocket Airsoft M130 AEG Spring - Japanese Black Steel

Rocket Airsoft M130 AEG Spring Japanese Black Steel. One of our most popular airsoft upgrade springs! Very high quality steel made spring to get your gun running above 400 FPS (420-430 approx). Fits in all standard gearboxes. This is your heavy upgrade spring strength for custom 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.