SilencerCo's ASR (Active Spring Retention) Mount technology facilitates attachment via a variety of different flash hiders, muzzle brakes, and direct thread mounts. The ASR Mount is compatible with all ASR muzzle devices, allowing you to use one convenient mounting system for various suppressors. Once shouldered, the locking ring ensures the suppressor will not rotate or work itself loose under a heavy firing schedule. This model is compatible with: Harvester Big Bore 338, Omega 300, and Hybrid.