The Leupold steel standard bases and rings are the most versatile of any mounting system we offer. The rear ring is secured by windage adjustment screws, allowing the scope's internal adjustments to be reserved for precise sight-in. Additionally, shims can be used for gross elevation adjustment, reserving the scope's elevation adjustment for bullet drop compensation dial applications. Fits- Remington Model 7 (serial number higher than 762,800 on stainless models or 773,800 on blue finished models), Remington 600/660 and 673 Guide Rifle, Remington 700/721/725/40X (Right Hand, SA) (also BSA Monarch, Mossberg 1500/1700, Remington 700 Muzzleloader, & Ruger M77 Round Receiver), Remington XP-100.