This is a Leupold Ring known as the LRW, model 120977.
Leupold LRW cross-slot rings are built from Strike Forged Steel" made in America to deliver unmatched durability and strength. Leupold CNC machining ensures perfect alignment to Weaver-style bases and the anti-slip grooves eliminate the need of lapping. LRW ring screws with Nylok won't back out under recoil or vibration.
Features:
Engineered specifically to match up with cross-slot bases
