Our newest addition , designed to fit within free float forearms with a internal dia. of 1 5/8's . Suppressor is 9 inchs long and as quiet as any 5.56 can I've ever seen . This suppressor is also the one which we are debuting our new mono core internal . This is a great advantage when it's time to clean the suppressor . We're able to bring the advantages of a mono core design to assault rifle calibers by incorporating a unique inconel blast chamber . Suppressor is shown an a Velocity Arms .22 upper with a 4.5 in barrel inside a RRA forearm . This is done to keep std velocity .22 rounds at subsonic velocity's [ about 1 in 5 MiniMag's will go supersonic] It's also done to add an incredible amount of cool factor Obviously , this can be built as an integral on any caliber upper , done to give a min. 16 in OAL to the upper .