The Ula class is a Norwegian submarine type which was assembled in Germany in the late 1980s and early 1990s. The class, consisting of 6 vessels, is currently the only submarine type in service with the Royal Norwegian Navy.
The Ula class submarines are among the most silent and maneuverable submarines in the world. This, in combination with the relatively small size, makes them difficult to detect from surface vessels and ideal for operations in coastal areas. The Ula class submarines are regarded as both the most effective and cost-effective weapons in the RNoN.
Information courtesy of wikipedia