Prepare your semi to be Ready for the Road Ahead , with the Tramec 32" x 9.5" Smile Shaped Bracket Below Steel Universal Air Tank that provides ample storage space for compressed air. This solid-steel tank stores compressed air that can be used to actuate a vehicle's air brakes, improve suspension, or operate air-powered attachments. Engineered with an automatic drain valve controlled by a pressure switch. FleetPride is your First Click in Heavy Duty .