Surefire snuck out two new 5.56mm suppressors at Modern Day Marine Expo. The Mini and the Micro are stubby little suckers that add barely 3.6 and 2.6 inches to a weapon's muzzle but cut down weapon signature and improve unit communication.
The Mini was designed for a 14.5" barrell and the Micro was designed for the 16.5"-and-up-club. We've heard they give considerable sound attenuation for their size on these barrel sizes. Surefire says you can go shorter to make SBR work without earpro comfortable, or at least bearable in most situations. Just don't expect to hear a pin drop when blasting through a room with a 10.5" barrel.
The two little guys come with Surefire's fast and solid threadless Fast-Attach system that requires the use of one of their muzzle breaks, flash hiders or compensators. No price, yet.