The Sandman series suppressors are excellent in the quiet and quick-detach repeat-ability department. They are also a heavy use/ High-heat silencer with their baffles made entirely out of stellite. As you might guess from the name the Sandman S is the Shorter of the two Sandman suppressors/silencers from Dead Air. The S being shorter, many people use them on 5.56, 300 blk 6.8 etc but it will work on 30 cal rounds up to .300 win mag. But on the larger calibers it will not be quite as quiet as its longer brother the Sandman-L.