Caliber: 5.56 NATO. This is the first M4 variant rifle from IWI U.S. The barrel is 16" 4150 Chrome Moly Vanadium HB, 1:8" twist, 6 RH grooves. The gas system is a mid-length direct impingement. The overall length is 33"–36.25". The weight is 6.9 lbs. without a magazine. The rifle has a 15" free-float handguard, B5 Systems stock, and grip. It was one 30-round Magpul PMAG. It is manufactured and assembled at the IWI U.S. facility in Middletown, Pennsylvania.