19.5mm bolt carrier group for Viper GBBR AR15

19.5mm x 60mm cylinder volume

Stratos telescopic cylinder system

Real firing pin retainer

S45c Steel CNC made bolt carrier

7075 T6 CNC made nozzle and cylinder, and valve

Music wire high strength springs

Bolt carrier group weighs 320g

Stronger recoil and high gas efficiency

ETA  September 2024

Free shipping for a pre order customer