The TREK-II is a compact and rugged threadmount suppressor for 5.56MM rifles and is suitable for full auto and shorter barrel (10.3" or greater) carbines. The TREK-II is made of rugged 17-4 stainless steel, with non-welded construction. New design allows for easy pinning to 11" or longer barrels to meet non-SBR overall length requirements.SpecificationsCaliber5.56mmSound Tested136dB 5.56mm Daniel Defense(R) - 16"Diameter1.5"Overall Length5.7"Weight16.1 oz.Mount Type1/2-28 ThreadsTube Material17-4 Stainless SteelFull Auto RatedYesTube FinishBlack High-Temperature Cerakote(R)