The cantilever mount is designed for mounting telescopic sights with 30mm tubes onto a flattop style AR-15 rifle. The 2-inch offset of this cantilever mount positions the scope in a forward location, allowing the correct eye relief and head placement on an AR-15.
The cantilever ring mount positions the center of the riflescope tube at a height of 1.45 inches (37mm) from the base.