Nobody makes bases to fit as many guns as Weaver. Yet each base is machined to tight tolerances for a custom fit. They're designed to fight the effects of recoil with a square cut notch that precisely mates to the sturdy cross bolt in every Weaver Detachable Ring. Custom hardened fastening screws come with every Weaver base.

2 of these are required to mount a scope

Fits:
Browning A-Bolt, A-Bolt 22 Stalker and Medallion, front or rear
Browning A-Bolt WSSM, front
Browning BBR long and short action, rear
Cooey 71, rear
Enfield cut down, rear
Marlin MR7, rear
Ruger 44 Magnum Deerstalker and Carbine, rear
Sears 53, rear
Winchester 70 long and short action with same hole spacing, rear
Winchester 70 Coyote SA, rear
Winchester 670 and 770, rear