This part is the replacement water line for your refrigerator. It is a long plastic tube, which is 5/16 of an inch in diameter. If your refrigerator is leaking, or if it will not dispense water or ice, you may have a damaged water line. When you replace the water line, you may want to pick up a new water tube union as well. You can use a utility knife to cut the old water line where it is damaged, and use the union to attach the new water line to the old one. This tubing is sold individually and is an OEM part.