Detachable Top Mount Base - 35M Matte BlackManufacture ID: 48500Nobody makes bases to fit as many guns as Weaver. Yet each base is machined to tight tolerances for a custom fit. They'redesigned 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.Warranty: Weaver?s Limited LifetimeWarranty: 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 forshipping..