Designed to accommodate firearms with unique integral mounting systems, these ringmounts are a high quality alternative to ringmounts sold by firearms manufacturers and as a no-tap mounting method for most .22 rimfire rifles with an 11mm, 13mm, 3/8" dovetail rail. Leupold ringmounts feature superior integrity and tighter tolerances because they are machined from solid stock. Also available in Extension rings to provide 5/8" of additional fore and aft ring spacing. Use as a high-quality alternative to ring mounts sold by firearms manufacturers and as a no-tap mounting method. Because these rings are machined from solid steel, they offer superior integrity and tighter tolerances. Features: Forged and machined steel construction Versatile, and available for many different rifles Use as a high-quality alternative to ring mounts sold by firearms manufacturers and as a no-tap mounting method for most 22 Rimfire rifles with an 11mm, 13mm, or 3/8 inches dovetail rail Superior integrity and tighter tolerances because we machine them from solid stock