• The Delta IV is a strategic ballistic missile firing nuclear propelled subm
The Russian Navy operates seven Delta IV class strategic missile submarines. The submarines operate in the Northern Fleet and are based at the Saida Guba Naval Base.

The submarines were built at the Severodvinsk Shipyard from 1981 to 1992. The first of class, K51, was commissioned in December 1985. In Russia, they are referred to as the Delfin or Dolphin class Project 667 submarines.