A full line of forging tools make expanding HVAC pipes easy. Preserving the ductility of copper/aluminum during forging to prevent cracks and leaks. 5 kinds of sizes to choose fromwith the most common HVAC pipe diameter: 1/4 inch 3/8 inch 1/2 inch 5/8 inch 3/4 inch. Suitable for hard and soft copper standardized crimp kit, easy to solder. < p>The forging plug will provide ample stamping depth to achieve a perfect fit. Features: Made from high quality, durable materials. Easy to use and good performance, your good helper for work and life. Sufficient quantity, complete specifications, perfect to complete your works. When using installation of the air conditioner, expand the copper pipe to connect the two copper pipes with each other. (It needs to be installed on a hand drill). Material: bearing steel, blackened surface treatment. Color: black. Size: 3/4 inch (19 mm), 5/8 inch (15.9 mm), 1/2 inch (12.7 mm), 3/8 inch (9.5 mm), 1/4 inch (6.3 mm). Shank Model: 6.35mm Hex Shank. Package Content: 5 x Tube Expander. Note: the data is manual measurement, please allow 1-28cm error, due to differences between light and screen, there will be a certain color difference, the specific received in kind prevail.