Caliber: 5.56 mm (.223 caliber) – Length: 2.70 inches – Offset porting delivers greatly reduced recoil impulse and muzzle rise so the weapon tracks straight back to keep you on target for faster shot-to-shot recovery – Multiple bearing surfaces for superior suppressor alignment – Precision machined from US mill-certified heat-treated stainless steel bar stock – High-precision single-point cut barrel threads for optimum thread interface – Inspected for all critical dimensions including concentricity and alignment – Pilot holes for tuning of muzzle brake and to pin-and-weld on short-barreled rifles – Black Ionbond DLC coating provides maximum protection against harsh environmental conditions and facilitates cleaning after extreme use – Serves as rock-solid mounting adapter for SureFire SOCOM Series sound suppressors – Labyrinth seals prevent carbon buildup on suppressor lock ring indexing system – Installation requires no permanent modifications for M4 / M16 / AR15 type weapons