Product Features1. High Quality Material: Made of bearing steel, blackened surface treatment, which is rugged and durable.2. Great Perfomance: Preserve the ductility of copper/aluminum during die forging to avoid cracks and leakage. A full range of forging tools makes it easier to expand HVAC pipes.Suitable for hard-to-reach corners and tight spaces.3. Tool Set: 6 piece set, with the most common HVAC pipe diameter: 1/4inch,3/8inch,1/2inch,5/8inch,3/4inch,7/8inch.Sufficient quantity, complete specifications, perfect to complete your work needs.4. Easy to use: When installing 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).Easy to use, your good assistant for work and life.5. Application: Suitable for hard and soft copper standardized, easy to braze swaging set. The forging stopper will provide a large swaging depth to achieve a perfect fit.Package Included: 6 x Tube Expander