The water supply tubing is made of plastic and goes between the water inlet valve and the ice maker inlet tube. The tubing is 8 1/2 feet long and 1/4” in diameter. The water supply tubing transports water to the ice and water dispensers. If there is no water going to the ice maker, the refrigerator is leaking, or if the ice and water dispensers are not dispensing properly, you may need to replace the water supply tubing. This is an OEM part directly from the manufacturer. Please remember to shut off the water supply and to disconnect the power to your refrigerator before starting your repair.