This item converts 3/8" dovetails to 7/8" Weaver rails. The bottom of these mounts attaches directly to the 3/8" dovetail that are commonly found on many .22 rifles and air rifles and the top rail provides a 7/8" industry standard Weaver style rail. Converting the 3/8" dovetail groove to an industry standard 7/8" Weaver style rail will provide you with a much larger selection of optics to choose from. These mounts screw right on making for a very easy installation. Machined to tight tolerances for a custom fit.

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