Golf R. Engine Coolant Thermostat Housing Seal. Engine Coolant Thermostat O-Ring. Engine Coolant Thermostat Seal. O-Ring. Thermostat Housing Gasket. Engine Coolant Thermostat Housing Gasket. Engine Coolant Thermostat Housing Seal. Engine Coolant Thermostat O - Ring. Engine Coolant Thermostat Seal. Thermostat hsng seal. Thermostat unit seal. WASHER. Included with: Thermostat unit.