Ultimate Arms Gear Tactical Machined Aluminum QD Quick Detach Weaver - Picatinny 7/8" To Dovetail 3/8" 11mm Rail Adapter Mount - Pack Of 2 Made From Aircraft Grade Aluminum - Black Anodized Convert Your Weaver/Picatinny (7/8") Rail Base Into A Dovetail (3/8") Base So You Can Use Your Favorite Dovetail Accessories Easy Installation - "QD" Quick Detach Thumbnut Each Adapter Is 1.2" Long - 2 Adapters Included