TBA Suppressors MP15SD. Built on a Smith and Wesson M&P 15-22. Stupid quiet. How quiet? Lock the bolt back on a 15-22, shoulder it, drop the bolt, that’s what it sounds like. Generation 2, stainless monocore permanently attached to barrel for 16.1″ overall length, and ease of service. Comes apart in no time at all. Muzzle broached for disassembly with included allen wrench. Ported barrel for subsonic muzzle velocity with brick pack ammo.