Machined steel construction. Remove and reattach a scope 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 characteristic that distinguishes the quick release mount system from the dual dovetail and STD systems is the ability to remove the scope from the rifle and reattach it without the loss of zero (within 1/2 MOA). Machined steel construction supremely-close machining tolerances.