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. – Fits: – Browning Bolt Actions Hi-Power (older models) (rear base) – CIL 972-C (rear base) – Colt 57 (rear base) – H & R 300 301 330 370 (before 1973)(rear base) – Herters J9 (rear base) – Marlin 455 (rear base) – Mauser (including FN HVA and Swedish) 98 Large Ring (rear base) – Modern Muzzleloading LK-93 Wolverine Legend (round receiver) (front and rear base) – Musgrave Mark III and Mark IV (rear base) – Parker Hale 1000 1000C 1100 1200 1700 (rear base) – Sears 50 51 (rear base) – Springfield 03-A3 (front base) – Voere 2150 2165/1 2165/3 2165/4 (rear base) – Weatherby Models with FN actions (rear base)