Hexagonal Shank:These expanders are designed with hexagonal shank and are suitable for installation on various manual electric drills. Function: Preserving the ductility of copper/aluminum during die forging to avoid cracks and leakage. Application: Perfect for installers. Good performance and long life, full range of forging tools makes it easier to extend pipes. Material: It is made of high Bearing steel materials, durable and easy to use, your good assistant for work and life. Note: Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Thank you Please allow 1-3cm measuring deviation due to manual measurement.