Rocket Airsoft M150 AEG Spring

Rocket Airsoft M150 AEG Spring. Silver type upgrade spring that is non-linear.  Fits in all gearboxes.  A higher FPS than usual for heavy duty upgrades.  FPS will be just below 500 FPS.  We don't recommend this spring unless you know what you're doing.  For heavy DMR or reinforced gearbox builds only.  (please note: packaging may be generic or labeled as 'Rocket Airsoft', but is made by SHS OEM)