This is the replacement upper spray arm water supply hose for dishwasher. It is made of white plastic and has a connector piece on each end. This hose supplies water to the upper spray arm, so it can be sprayed onto your dishes when the dishwasher is running. The main reason to replace the supply hose is if it is cracked and leaking, and the spray arm is not getting enough water. This part is sold individually and is a genuine OEM part sourced directly from the manufacturer.