The m4sd flash comp optimally combines the functions of three traditionally separate classes of devices- muzzle brakes, tactical compensators, and flash suppressors.Compatible with the m4sd series gate-lok suppressor interface the flash comp provides a sacrificial baffle to increase the service life of your silencer.It is also pre drilled, and 2.25 length for 14.5 to 16 permanently attached, non-sbr, m4 carbine builds.Extreme durability, low concussion flash and recoil reduction are the wave of the future- the flash comp provides an elegant solution to a complex problem.Includes shim set and over-travel stop washer (for mounting to suppressor).Finish: Black NitrideModel: M4SDMaterial: 17-4 Stainless SteelThread Pattern: 1/2"-28 tpi