PolarStar - Fusion Engine Nozzle for M4 (Silver: 446-514 FPS) shotgun Blowback is a term used

Blowback is a term used when the slide cycles back and forth when a shot is fired

Steel reinforced rivet attachment

high torque

To reduce weight and increase the FPS a strong 45° polycarb piston is used with an oversized o-ring to create a perfect air seal to boost the FPS of the M28

3000 rnd Automatic Box Magazine

PolarStar - Fusion Engine Nozzle for M4 (Silver: 446-514 FPS) shotgun Blowback is a term usedOur series of Fusion Engine air nozzles allows you shift the velocity range of your rifle up or down to best meet your requirements. Nozzles are easy to install and typically take less than 5 minutes to change out on most models from start to finish. Each nozzle is machined from aluminum and comes with both the internal and external o rings. The nozzles are color coded with a hard coat anodizing for easy identification. Results with a . 20g BB using a