This lot of 2 cooling fans are designed for use in IBM X3550 1U servers. The fans have a fan diameter of 40 mm and are compatible with IBM products. They are model X3550 and have part numbers 26K8083 and 26K8082. This cooling fan assembly is an essential component for keeping your server running cool and efficiently. It is suitable for use in CPU fans and heat sinks and can be easily installed. Don't miss out on this great deal for a lot of two IBM X3550 1U server cooling fans.