Leupold IMS - Integral Mounting System, 1 Piece Base, 30mm, fits Picatinny, Black

The Mark IMS family easily eliminates the two most common issues faced when mounting standard riflescopes to AR-style rifles; scope height and eye relief. This model is designed to fit your AR's MIL-spec 1913/Picatinny rail and any scope with a 30mm maintube. It also accounts for the extra space needed for modern bolt actions.