The US Army proudly issues this as their standard rear flip up sight. The sight mounts to the rear of the rifle and can be folded down when not in use or if you are using an optic as a primary aiming sight. The sight securely mounts to and Picatinny compatible rails. There are windage and range adjustments from 200-600 meters.
Be aware that Matech does not guarantee any of their products that are not bought directly from Matech. However, this sight does come with the Venture Surplus Satisfaction Guarantee.