Leupold 1in RM CZ 550 Rings - Medium - Use as a high-quality alternative to ringmounts 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. Use as 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, or 3/8" dovetail rail. Superior integrity and tighter tolerances because we machine them from solid stock. Versatile, and available for many different rifles. Forged and machined steel construction.