Rosenlewin Urheilijat-38, RU-38 for short, was a sports club based in Pori, Finland. It was founded in 1938 by the W. Rosenlew Company. The club was best known by its football and ice hockey sections. In 1967 RU-38 merged with another local club, Karhut, forming a new club named Ässät. The athletes of RU-38 were usually semi-professionals. They had a job at the company's factories and could use their working hours in training.