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. No.47M mountSpecifications and Features:Weaver Top-Mount No. 47M 48503 Precision builtTight tolerances Square cut notch Aluminum Matte BlackFits: Browning A-Bolt, A-Bolt 22 Stalker, BBR Long Action & Short Action - Rear Base Only Browning Medallion - Front and Rear Base Enfield (Cut down like a Winchester 70) - Rear Base Only Marlin MR7 - Rear Base Only Sears 53 - Rear Base Only Winchester Model 70 - Rear Base Only And Others