The quick release, weaver style ring mounts features a durable steel construction and a black matte finish. Can be used with Leupold's PRW bases or any other Picatinny-style mount rails.Detachable mounts, crafted from durable steel. The updated industrial design gives you more contact with the base for added stability and easier installation. Features: Bases are available for many popular rifle models Our cross-slot base rings are engineered specifically to match up with cross-slot bases, we recommend you mount these incredibly stable rings on firearms such as tactical shotguns with built-in mounting rails QRW mounts bring Leupold accuracy to the cross-slot format, they feature steel detachable accuracy mounts that are based on the familiar cross-slot design, use the QRW mounts to achieve detachable accuracy