b'*Direct thread mount includedLENGTH.5.3 DB REDUCT 38dB .22LR, 32dB 5.56mm (Taper Mount)WEIGHT.8.5oz MATERIAL.Nitrided 17-4SSDIAMETER1.1 MSRP$549CALIBER5.56mm RATED FOR.17HMR, 5.7mm and .22 calibers'