The QR mount promises repeatable accuracy. Remove and reattach a scope using our QR mount and still return to within half an inch of the original point-of-impact on the target. Turn the lever forward and an eccentric on the lever shaft engages the base of the ring, pulling it down and forward on the base, locking it solidly into its “zero” position. The key is super-close machining tolerances at the heart of the patented lever mechanism. Machined steel construction. Must be used with Leupold QR rings (sold separately).