Sequoia. A component which prevents a leak at The Engine Coolant Inlet Housing. Engine Coolant Thermostat Gasket. Engine Coolant Thermostat Housing Seal. Engine Coolant Thermostat O-Ring. Gasket for Engine Coolant Water Inlet. O-Ring. Thermostat Housing Gasket. Housing. hsng o - Ring. Inlet Flange. unit o - Ring. Water Neck. Included with: Inlet pipe, Thermostat, Thermostat Housing, Thermostat unit, Thermostat unit Part cannot be reused/reinstalled, Water Inlet, Water Inlet Part cannot be reused/reinstalled.