5Pcs Tube Expander Hex Handle Bearing Steel Air Conditioning Copper Pipe Extension Tool 5Pcs Tube Expander Hex Handle Bearing Steel Air Conditioning Copper Pipe Extension Tool Made of high‑quality bearing steel material, with high strength and hardness, good wear resistance.​ Can maintain good ductility during the expansion process, which can prevent the copper pipe from cracking and leaking.​ The kit contains 5 sizes of expanders, suitable for different air‑conditioning copper pipe expansion.​ 5Pcs Tube Expander Hex Handle Bearing Steel Air Conditioning Copper Pipe Extension Tool Item Type: Tube Expander Material: Bearing steel Surface Treatment: Blackening Shank Diameter: 1/4in (approx. 6.35mm / 0.3in) hex handle Specifications: 3/4in (approx. 19mm / 0.75in), 5/8in (approx. 15.9mm / 0.6in), 1/2in (approx. 12.7mm / 0.5in), 3/8in (approx. 9.5mm / 0.4in), 1/4in (approx. 6.3mm / 0.25in)​