The Alpha Direct Thread Mounts are a simple solution to attach SilencerCo silencers to any firearm. Compared to QD mounts, a Direct Thread Mount shortens the overall length of the suppressor. Compatible with fixed rifle barrels. Threads are 1/2-28. This thread mount is not for use on pistols with unlocking or moving barrels. Using this mount on a pistol can result in damage to the suppressor.