The Ultra-Light Aluminum Frame is constructed of 13/4 " ID round aluminum tube. This tube is milled to our specifications and is a Stoneblaze exclusive. The unique material allows us to produce a frame which is equal in strength to our proven steel frame, yet it is 40% lighter in weight. The Ultra-Light Aluminum Frame features angle fittings which detach from the main tubes. Ideal for use on horseback, in an airplane, or in a boat/canoe.