With its rounded corners and edges, the Markins Lens Plate PL-250 is a 9.8" long plate that is designed to fit to the bottom of a tripod foot on telephoto lenses. With a 3/8"-16 and 1/4'-20 threaded mount, the lens plate attaches to the tripod foot. The dovetail design can mount into an Arca-type clamp, or if one is not available, a 1/4"-20 threaded socket is located on the bottom. The plate is constructed from Duralumin that has a hard-anodized, scratch-resistant surface.