Tier One 11mm Dovetail Rings Black 30mm Medium. Made from tough yet lightweight aerospace Aluminum 7075T6 these rings offer strength without the weight suitable for serious shooting enthusiasts. They come in Medium and High configurations with stainless steel hardware and in-house manufactured screws for meticulous accuracy. The rings undergo a deburring process and are finished with a hard black anodize to a mil-spec 30 microns. With these rings expect tighter groups and improved performance no lapping required. These rings are not recommended for Magnum or high-recoil calibers for those applications they always recommend a high quality picatinny rail. Specifications for Tier One 11mm Dovetail Rings: Manufacturer: Tier One Finish: Anodized Quantity: 1 Fabric/Material: Aluminum Color: Black Package Contents: Tier One 11mm Dovetail Rings Nil Tier One T111D30M: 11mm Dovetail Rings Black 30mm Medium