SureFire Suppressor Adapter/Muzzle Brake, fits M4 / M16 weapons and variants with 1/2-28 muzzle threads. It greatly reduces both recoil impulse and muzzle rise so that the weapon tracks straight back to keep you on target for faster shot-to-shot recovery. The patented Impulse Diffusion design minimizes side blast and rear-directed concussion effects. Precision machined from US mill-certified heat-treated stainless steel bar stock including high-precision single-point cut threads for optimum thread interface the SFMB-556-1/2-28 muzzle brake has a black Ionbond DLC coating to provide maximum protection under harsh environmental conditions and to facilitate cleaning even after extreme use. The SFMB-556-1/2-28 also serves as a rock-solid mounting adapter for SureFire SOCOM Series 5.56 mm Fast-Attach suppressors. A rear labyrinth seal minimizes potential carbon buildup in the indexing system and facilitates suppressor removal after extended firing.