New The one you will receive will be in the org packaging $50 shipped I will also take trades I have several sets so you can buy more then one. U.S. Army Standard-Issue Backup Sight For M4/M16A4 MATECH BUIS Leaf Sight is current issue to US Military. This Windage and elevation adjustable flip-up rear iron sight is battle tested with a low-profile design. Folds down out of the way when not in use. Will fit under a Trijicon ACOG riflescope. Elevation adjustable to 600 meters. Windage: 1/2 MOA Elevation: 0-600m NSN 1005-01-484-8000 , PN# 12996812 Current U.S. Army standard-issue backup rear sight flips up instantly at the touch of your thumb when primary sight fails or tactical situation makes iron sights preferable. Designed in conjunction with Picatinny Arsenal engineering staff and rigorously tested at Fort Benning and Aberdeen Proving Ground for robustness, ease of use, and effective targeting out to 600 meters. Detent-locking lever lets you quickly switch to one of eight range settings: 200, 300, 350, 400, 450, 500, 550, and 600 meters. Adjust windage easily with grooved, A2-style windage knob and position markers on the back of the sight for repeatability of settings. Bright, white, laser etched numbers and markers are clearly visible even in low light. Rugged machined steel construction ensures sight retains zero even under heavy, full-auto fire. Clamps securely to the rearmost slot of MIL-STD 1913 Picatinny or Weaver-style accessory rail on flattop receiver via simple but strong locking bar and bolt. Rounded corners and beveled edges further reduce danger of snagging on other gear when sight post is down. Regulates correctly with A2 front sight on any .223 5.56 rifle or carbine; instructions included for adjusting front sight post height to set exact zero. Designed to co-witness with most non-magnifying optical sights.