Rugged, Durable ConstructionAssembled using precision machined using both aircraft grade aluminum and steel.Adjustable Windage and ElevationUnlike many rear backup sights, this includes both windage and elevation adjustments to allow more precise long range work. This unit is actually modeled after the proven rear sight that is standard on carry handle rear sights. So you get the adjustability and proven design without the added bulk of the handle itself. Absolute Co-WitnessDesigned for AR style rifles and will co-witness with standard optics.Close Quarters and Long Range CapableWith dual apertures, one large for close range rapid target acquisition and another, smaller aperture for precision long range work.Backed by the NBS Limited Lifetime Warranty