This is a Gemtech Thread Adapter known as the 22 QDA chambered in 22 LR, model 12201.
The GEMTECH 22 QDA is a universal adapter for all rimfire silencers that allow attachment and detachment quickly and efficiently. The four lug muzzle device is threaded 1/2-28 to mount on all standard rimfire threaded barrels for maximum compatibility. The QDA mount is threaded 1/2-28 for use in all rimfire silencers in 22LR and 22MAG. The 22 QDA will allow you to switch firearms quickly and still maintain complete control.
Features:
The 22 QDA is not rated for use with ANY centerfire rifle calibers.
