Usually, the water line for the refrigerator connects up to the water line that is located beneath the sink, but it may also hook up to a water line that was expressly constructed for the refrigerator on the wall behind it. A shutdown valve with a male connection is often located beneath the sink in the line that supplies water. The fitting for the specified refrigerator line is a male connection, and it also includes a fitting. A female compression nut and a ferrule, which is a tiny tube that fits within the nut, are both components that are required to be used in order to successfully connect a smooth copper or plastic line to the fittings. As soon as these fittings are installed, you will be able to finish hooking up the refrigerator to the water supply.