HUXWRX Safety Company Flash Hider-QD 556, 1/2X28 Long (2.7), .223 Remington/5.56NATO, Flash Hider, Quick Detach Suppressor Mount, Compatible with HX-QD 556K, 556, 762, 762 Ti, Magnum Ti Suppressors, Black 2885 The Flash Hider-QD is designed to mitigate flash when unsuppressed. Flash Hider-QD 556 is compatible with HX-QD 556k" 556" 762" 762 Ti and Magnum Ti suppressors. NOTE: Larger caliber mounts are NOT compatible with smaller caliber suppressors. Smaller caliber mounts ARE compatible with larger caliber suppressors.