b'M4SD-L*Hammer Comp mount includedLENGTH.6.5 DB SPL131.7dB 16, 133.7dB 11.5 5.56mmWEIGHT.14.5oz MATERIAL.H900 & Nitrided 17-4SSDIAMETER1.5 MSRP$995CALIBER5.56mm RATED FOR.Full Auto, 22 calibers up to 220 swift'