EGW Mauser 98 Large Ring 3-Hole Scope Bases. Rifle bases precision machined from extruded aluminum with Picatinny slot-and-rail spacing that allows fast and simple changes to eye relief, plus great flexibility in scope choice. Accepts Picatinny or Weaver scope rings. Lightweight Tactical mounts have a milled center channel for weight reduction. Full-width cross-slots are gauged to MIL-STD 1913 specs to +/-.002". Machined from ultra-rigid, extruded 6061 T6 aluminum. Includes socket head TorxA(R) screws and wrench. EGW recommends 20 inch lbs of torque and a drip of blue loctite for mounting. Mfg: Egw