Detachable Top Mount Base 61S SilverManufacture ID: 48002Nobody 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 squarecut notch that precisely mates to the sturdy cross bolt in every Weaver Detachable Ring. Customhardened fastening screws come with every Weaver base.Warranty: Weaver’s Limited Lifetime Warranty: Blount warrants Weaver products to be free of defects in materials and workmanship for as long as it is owned by its original owner. Repair/Replacement will be done when returned without charge except for shipping.