LeupoldA(R) ringmounts are a high-quality alternative to firearm manufacturer ringmounts or as a no-tap mounting method for most .22 rimfire rifles with an 11mm, 13mm, or 3/8'' dovetail rail. This model is designed to fit a Ruger No. 1 & 77/11, and because these rings are machined from solid steel, they offer superior integrity and tighter tolerances. Nothing is more crucial than the link between your scope and firearm. That's why our mounts are every bit as rugged and dependable as the Leupold optics they secure. And with a huge variety of mounting systems to pick from, you're sure to find the perfect match for your firearm and style of shooting. Made in the USA an Mfg: Leupold