a USMC M16A4. Only difference is this Colt AR15A4 does not have a 3 round burst as it is not a class 3 item. Like new excellent condition only fired 60 times to sight in USMC 4x32 TA31RCO-A4CP Acog and hit a steel silhouette at 300 meters. Awesome packange and what some of you Jar Heads were probably using while enlisted.