The Send It Scope Tube Mounting Rings are specifically designed to allow owners of the company's innovative Send iT rifle-leveling system to attach their levels to all standard riflescope tubes. The rings are machined from aluminum, feature a matte-black finish and can attach levels to the tube vertically or horizontally. Rings are available to fit optic tubes with diameters of 1 inch, 30mm, 34mm and 35mm.