I purchased this for use on various lines, but primarily steel hydraulic line, stainless line, and occasion copper/nickel brake and fuel lines. This unit functions very well, with comparable results to the higher-priced competitors. The radius and diameter markings printed on the tool handles are accurate and help to simplify calculations for complex bends. I have had no issues with kinking or crushing of the tube, regardless of the tube material used, and am quite happy with this tool. The long handles also make the work much easier than many smaller units, a big deal when working on stainless hydraulic/pneumatic lines.