Genuine OEM Audi Coolant Hose, part number 8K0819377AC. This hose is part of the vehicle's heating and air conditioning system, responsible for circulating engine coolant to the heater core to provide cabin heat. It is located in the engine bay and connects to the heater core and other coolant lines. Constructed from durable, heat-resistant materials, it is designed to withstand the operating conditions of the heating system. Genuine OEM hoses ensure proper coolant flow and prevent leaks, maintaining the efficiency of the climate control system.