This is a Gemtech Flash Hider known as the QUICKMOUNT chambered in 556NATO, model 12145.
The NEW GEMTECH flash hiders are the culmination of user feedback" extensive testing" and decades of experience. The new flash hiders are more aggressive than ever to cut down on carbon build-up in your suppressor and to prevent it from getting stuck. All 5.56mm QUICKMOUNTS fit the M4-96D" G5" G5-T" SHIELD" HVT-QM" QUICKSAND and ONE suppressors.
Features:
Blank Firing Adapter groove
Quickmount lugs for use with all Gemtech 5.56MM and .30 cal suppressors
Precision mounting shim kit