The M4 was a French submarine-launched ballistic missile (SLBM) deployed on the nuclear s (except the Redoutable herself, which was not refitted).
They entered service on 1 May 1985. They were the first French MIRV-capable nuclear missiles, with six 150 kilotonne warheads.
They were replaced by the improved M45 SLBM missile which was in service aboard the .