Converts dovetail rails to a 9 slot Weaver rail * Also works as a riser mount that raises line of sight by 0.571inch * Bulit-in pointed stop pin and 3 clamping screws for extra holding power (needs to have predrilled receiver top to apply) * Reversible side plate to adjust fit between 3/8inch and 11mm dovetail rails * Great for use on .22 rifles, airguns and crossbows wth dovetail scope bases