Ade Advanced Optics 35mm Tactical Mounts/rings (Pair) for Rifle Scope Picatinny Rails on Three Sides 35mm diameter Standard with six sided hexbolts for maximum hold under extreme conditions and automatic weapons fire The mass of the mount ensure maximum thermal stability when working under extreme temperatures Picatinny rails on three sides for ease of attaching other items. Height: 35.5mm from the bottom to the center of the ring.