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. Each aluminum IMS cantilever design mounts directly to the firearm’s Mil-Spec 1913/Picatinny to raise the scope and push it forward, eliminating the need for risers or specialized optics with shortened eye relief. Mark 2 Rail provides the same advantages as the Mark 1, plus the added benefit of easy-to-grasp ½" hex nuts on the crossbolts for quick release removal and installation. All Leupold IMS products are tested to endure the rigors of the field and are covered by the Leupold Full Lifetime Guarantee.
AR-15, Issue:11, Page:092
Big Book Catalog, Issue:73, Page:103
Sinclair, Issue:5B, Page:202