Each Weaver base is machined to the tightest tolerances for a custom fit. They are 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.Specifications and Features:Manufacturer Number:48504 Fits: Anschutz 1568 (rear)CIL 950 & 950-C (rear)Ithaca LSA-55 & LSA-65 (front or rear)Modern Muzzleloader Knight MK-85 & KB-92 (front or rear)Modern Muzzleloader T-Bolt flat receiver (front or rear)Sako Whitetail Hunter (front or rear)Savage 10, 12, 16, 510, 512 & 516 short-action (rear)Savage Striker pistol (rear)Savage 110 E/S, 111, 112 R/V/FV & 116FSS long-action (rear)Savage 210 shotgun made before 2003 (rear)Savage 10 muzzleloader (rear)Shilen flat-top receiver (front or rear)Stevens 110E (rear)Includes custom-hardened fastening screws for mounting