Caliber: 5.56 mm (.223 caliber) – Length: 2.67 inches – Patent-pending design provides over 99% flash elimination; virtually eliminates muzzle rise – Serves as rock-solid mounting adapter for SureFire SOCOM suppressors – Multiple bearing surfaces provide suppressor alignment and prevent tines from ringing inside suppressor – Precision machined from US mill-certified heat-treated stainless steel bar stock – High-precision single-point cut barrel threads for optimum thread interface – Individually inspected for all critical dimensions including concentricity and alignment – Ionbond DLC coating provides maximum protection against harsh environmental conditions and facilitates cleaning after extreme use – Labyrinth seals prevent carbon buildup on suppressor lock ring indexing system – Installation requires no permanent modifications to weapon – Made in the USA and backed by SureFire No-Hassle Guarantee