O-Ring fittings are designed for use with Allstar Performance all31130 inline Electric water pump and inlet port of all31159 Y-Block fitting. The key to success in a car building project is access to high quality, reasonably priced parts that get the job done right. Each Allstar part is the result of our dedication to research and development. Once a need is established, parts are designed and manufactured by talented craftsmen, many of whom are racers and hot rodders themselves. Many Allstar Performance parts are one-of-a-kind; you won't find them anywhere else