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 kit hard and soft copper standardized crimp plug, easy to solder. The forging plug will provide great depth of stamping to achieve a perfect fit. Features: 100% brand new and high quality. Made of high quality materials, durable. Easy to use and good performance, your good helper for work and life. Sufficient quantity, complete specifications, perfect to complete your works. When installing the air conditioner, expand the copper pipe to connect the two copper pipes between them. (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.