Drift off old sight using a hammer and punch or sight pusher tool, taking care not to damage slide. Loosen hexhead clamping screws with the Allen wrench provided. Slide into the dovetail groove. Center sight and tighten clamping screws using the short end of the Allen wrench as the handle. DO NOT OVERTIGHTEN the clamping screws. To adjust sight, slightly loosen clamping screws and apply slight pressure in direction of desired correction. Once windage adjustment is correct, apply thread lock to screws.