CALIBER:5.56MM NATO CHAMBER FOR 5.56MM AND .223 CALIBERUPPER RECEIVER:EXTRUDED ALUMINUM A4 WITH PORT DOOR/NO FORWARD ASSISTBARREL:16-INCH CHROME MOLYMUZZLE DEVICE:A2 FLASH HIDER / 1/2-28 THREADGAS SYSTEM:CAR LENGTH, WITH LOW PROFILE GAS BLOCKHANDGUARD:RRA 15 INCH RRAGE 3G HANDGUARD, M-LOK COMPATIBLEWEIGHT:4.25 POUNDSINCLUDES:BOLT CARRIER GROUP AND CHARGING HANDLE ASSEMBLY