BREEK ARMS PLAN B SENTINEL 5.56 NATO/.223 REM CAGED FLASH HIDER The Sentinel is a closed-tine, fully shrouded design for superior flash suppression and to reduce snagging on gear. Built for Plan B mounts and pin-and-weld builds, it delivers rock-solid alignment, compact length, and NVG-friendly signature reduction. SPECS Weight: 2.2 oz. Overall Length: 2.15" Material: 4140 Hardened Steel, Nitride Thread Pitch: 1/2 x 28 TPI Caliber: 223/5.56 Fast attach for Plan B suppressor mounts Engineered to be pinned & elded on 14.5" barrels to meet the 16" Federal minimum length requirement Mfg: Breek Arms