Anschutz Picatinny Scope Base 1761 Will accommodate picatinny style scope mounts for use with scopes, red-dots or many other sighting systems. Designed for model 1761 right hand or left hand ejection. Slides on to the 11 mm rail that is cut into the top of the receiver. The two brass tipped set screws go in the front and middle threaded holes in the rail. The one without a brass tip belongs in the rear threaded hole in the rail and the round smooth pin end will rest in the recoil slot that is cut perpendicular to the bore in the top of the receiver. Do not over tighten these set screws. 0 MOA Built in Elevation Length: 6.69" (170 mm) Width: 0.79" (20 mm) Height: 0.59" (15 mm) Weight: 2.29 oz (65g) Material: Aluminum