Upper Coolant Housing Built In Filler Hose For K Series K20 K24A1 Acura Rsx SiDescription: 100% Brand New, never been used Material: Aluminum & Stainless Steel The filler neck comes off the top of the housing and can be used to relocate the radiator cap to a higher point on the engine itself. The new location is the highest point of the cooling system and allows air pockets to easily escape during the coolant bleeding process. The Filler Neck comes with a standard hose fitting. This part will be very helpful on an engine that