Rosco Husky 12.5 inch 5.56 NATO barrel designed for AR-15 platforms. 4150 CMV steel with chrome-lined chamber and bore. Husky profile for heat mitigation and reduced barrel whip. 1:7 twist compatible with AR-15 platforms in 5.56 NATO. 12.5" length with phosphate exterior finish and standard .750 gas block compatibility. SOCOM-style Husky profile aims to improve reliability and longevity. Threaded barrel (thread pitch not specified).