It is made up of Molded injected plastic, with drain holes in the bottom to keep moisture away, no mounting screws are required, smooth finish for easy clean-up. The side drain makes the cup holder so convenient, there is no worry about having to empty the cup holder every time it rains or someone spills. Great for boat, yacht, truck, car, RV, game table, sofa, apartment, caravan, dashboard, and seatback. Dimensions: Top Diameter: 4-1/4''(108.0 mm); Bottom Diameter: 2-13/16''(71.5 mm). Package Includes Pack of 1 Marine City White Plastic Cup Holder Without Drain Hole.