Features: This product is made of fine material, it has a long service life, you do not need to change it often. When you need to install the air conditioners, you can use it to expand the copper pipes then make the two pipes interconnected. It is very easy to use it, and can save your time and energy. It is in small size, so you can take it with you to anywhere you want to use it. Please notice, this tool need to installed on the electric hand drill to use it. There are 6 size for you to choose, you can use the one you need.