MaxLine's patented semi-flexible tubing maintains its shape after bending, using compression fittings for efficient, leak-proof delivery of clean compressed air. With a HDPE inner/outer layer and a smooth aluminum center, MaxLine remains corrosion free for decades, can be buried underground and can be installed in half the time of traditional methods. Ideal for layouts with obstructions. Tubing can sweep/bend corners without elbow fittings. Designed to be used with compressed air and inert gases. 1” MAXLINE: Outside Diameter: 32 mm (1.26 in)