Yankee Hill 5 Slot Picatinny Angle Dovetail Mount - 2-1/8 Inch is a great mount when used with scopes, flashlights, and lasers. Accessories are mounted at a 45 degree angle. When used with scopes the iron sights remain visible. The 2-1/8 inch Angle Mount is made from aircraft quality aluminum and hardcoated to Mil. Specs for long lasting duribility. Measures 2-1/8 inches long. Uses a 7/64 ubcg Allen wrench.