The Leupold Integral Mounting Systems (IMS) family quickly and easily eliminates the two most common issues faced when mounting standard riflescopes to AR-style rifles; scope height and eye relief. From the Mark 1 to the Mark 4, each aluminum IMS cantilever design mounts directly to the firearms MIL-spec 1913/Picatinny to raise the scope and push it forward, eliminating the need for risers or specialized optics with shortened eye relief. This model features a 20 MOA cant. All Leupold IMS products are tested to endure the rigors of the field and covered by the Leupold Lifetime Guarantee.