The raw stainless ZEROED 556 makes no compromises on sound suppression without beating up your wallet. Made from the same 17-4 stainless steel as the regular ZEROED 556 this raw stainless variant provides the same full auto rating to combat load strings of fire between cooldown periods. Standard 1.375-24 HUB threads let you use almost any direct thread or QD mounting system you prefer. Suppressor features a 3/8 square drive in the non-removable front end cap for easy HUB removal and attachment. – Organic (raw stainless) Finish – Starting as a smokey bronze color the raw uncoated stainless steel patinas with use making each organic suppressor unique in its constantly evolving pattern and coloring. Color and patina will change depending on number of rounds shot caliber type of firearm oiling and handling; Photos shown are not a guarantee of how the suppressor looks will change. – Raw finished suppressors do NOT include a direct thread or QD HUB mount but can be added. – Specifications – Caliber .22 ARC 4.6x30mm 5.56x45mm 5.7x28mm – Finish Raw/Uncoated – Weight 17.4 oz / 15.2 oz w/o mount – Length 6.5 / 6.2 w/o mount – Diameter 1.58 – HUB Compatible Yes – Material 17-4 Stainless Steel – Attachment 1.375-24 HUB Mount Compatible – Minimum Barrel Length 5.7x28mm: 5 / 5.56mm: 10.5 – Full Auto Rated Yes – Bore Diameter .224 Caliber