This Mark AR mounting system features an aluminum 1-piece integrated base and rings. It is designed to fit a Picatinny rail and any scope with a 1″ maintube. Leupolds tactical Mark AR family of mounts gets your scope at the right height and the right eye relief while providing one of the most rock-solid mounting solutions in the business. The Mark AR mount features a 5-bolt design for a secure hold, and 3 lugs on the bottom to withstand any kind of recoil.