The 085807B Geissele Automatics Super Gas Block is a low-profile design meant to comfortably fit under most free-floating handguards. Meticulously investment cast from 17-4 precipitation hardening stainless steel, the gas block boasts exceptional corrosion resistance and robustness to endure thousands of rounds without failing. The accompanying instructions cater to both the standard set screw installation method and Geissele\'s exclusive \"Bombproof Installation\". The latter utilizes a provided coil pin that securely locks the gas block onto the barrel, rendering it immune to sliding or twisting regardless of the operating conditions. Furthermore, the Super Gas Block comes bundled with a stainless steel dowel pin facilitating effortless alignment of the SGB with Geissele CHF barrels, guaranteeing perfect congruence with the gas port.Included with your purchase, you will find a Bombproof Coil Pin, two set screws, a Gas tube coil pin, and a Stainless steel barrel alignment pin.