Weaver 30 mm Grand Slam Ring Steel Matte Black. Many companies have copied the simple design of these steel rings. Weaver is proud to say that our forefathers in the business started just that; making the best steel rings you could possibly buy. These rings continue to be made today. What really makes these rings great is the fact the individual rings are made from an incredibly strong steel - not cheap cast or stamped steel. Inside each ring is a cross-shaped bar ensuring that the top bar always sits at the perfect height and keeps the scope properly aligned. The name "Grand Slam" rings were coined because of their superior performance in reducing recoil and maximizing accuracy in essentially any type of gun you could ever want to use. Specifications for Weaver Grand Slam Ring Steel: Manufacturer: Weaver Finish: Matte Tube Diameter: 30 mm Condition: New Color: Matte Black Features of Weaver Grand Slam Ring Steel Solid Steel Construction Precision Locking System Torx Head Hardware Package Contents: Weaver Grand Slam Ring Steel Weaver 49310: 30 mm Grand Slam Ring Steel Matte Black