Air Boom's Air Bar is constructed of 6061 aerospace grade Aluminum. The single crossover bar is 2 3/8? outside diameter with (4) 2? outside diameter support legs. Air Bar's feet use the same state of the art feet as our Air Boom Tower. Our design allows for mounting at any angle with the front and rear feet. The foot base is 3? in diameter (round) and has 1 – ? stainless steel stud (center) per foot. This eliminates any connect the dot cracking that occurs with multiple screw holes per foot. Being structurally superior is only one plus, this design hides all mounting hardware and provides the cleanest, best looking mount known to boarders.