My suppressed unit is a Walther ppk's in .22 lr with a pp barrel press fit on it, then threaded and the can attached.

Small package, quiet and absolutely reliable.

The BATF has the right to check the can and accompanying paperwork [ tax stamp ] anytime they feel like it. I welcome their check if they so choose. Doesn't bother me one bit and I'm not about to let their ability to check deny me of toys I enjoy.