TacFire .22 Crossbow Airgun Scope Rail Adapter Riser 3/8 inch 11mm Dovetail to Weaver Converter w/Stop Pin, 3 Secure Screws, T6 6061 Aluminum TacFire Official Product ,this is a rail adapter mount that converts 3/8" dovetail to Weaver rail One piece body made of solid aluminum alloy to withstand shock and recoil .Fits 3/8" dovetail mounts, rails and bases as commonly found on air rifles, paintball markers, rim fire rifles and crossbows Built in pointed stop pin can be applied when needed and upgraded 3 clamping screws for better holding power against spring action airguns .Raises line of sight by 9/16inch(14.3mm) Clamps and tightens using included Allen head wrench. Top rail is 4 inch long. Clamping bottom is 3 inch long . Weight : 2.2 oz . Finish :Anodized Black