The Yankee Hill 3 Slot Picatinny Angle Dovetail Mount is great when used with scopes, flashlights, lasers etc. Accessories are mounted at a 45 degree angle. When used with scopes the iron sights remain visible. Made from aircraft quality aluminum and hardcoated to Mil. Specs. 1-3/16 inches long. Uses a 7/64 inch Allen wrench.