Smoothly bend copper, brass, aluminum, and thin-wall steel without denting or collapsing your tube. 3-Size channel design accommodates 1/4", 5/16" and 3/8" O.D. tubing. Calibrated easy-to-read markings with a 0-180 degree angle adjuster for creating a variety of bends. Rugged aluminum alloy construction with a durable, baked enamel finish. Ideal for brake and fuel line, plumbing, heating & cooling, refrigeration, and hydraulic line applications.