This is a Leupold Ring known as the QR, model 49974.
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.
Features:
Forged and machined steel construction
Versatile
