A short and extremely durable suppressor. The HX-QD 556k is built with proven Flow-Through technology, delivers sub-140 dB performance, is full-auto rated and easily passes the USSOCOM Reliability Stress Test. Unlike traditional suppressors that manage trapped gas, intense heat and pressure with blast baffles, OSSs Flow-Through technology redirects expanding gases forward allowing us to use 17-4 stainless steel deflectors and internal Grade 5 Titanium coils. The result is a remarkably cooler and extremely durable suppressor. The HX-QD 556k has a fully-welded outer body made of 17-4 heat treated stainless steel coated with C-series high temperature black Cerakote.