The latest addition to the HELIX line, the HX 556 is an integrated flush mount system built with titanium, stainless steel and cobalt. The HX 556 dramatically reduces backpressure, blowback, sound and flash signature, and is full-auto rated. A self-tightening mounting device, the STS-Muzzle Brake (1/2 x 28 TPI), is included with each suppressor.
Currently, additional OSS STS-Brakes are not available from OSS. However, with the purchase of a separate STS Flash Hider, the HX 556 can be quickly switched between your 5.56 guns. Just thread the HX 556 onto the STS Flash Hider, hand tighten and you’re ready to shoot.