The M4 was a French Submarine Launched Ballistic Missile (SLBM) deployed on the nuclear Le Redoutable class submarines (except the Redoutable herself, which was not reffited)

They entered service on the 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

M45 SLBM

The M45 SLBM is the current standard French Navy's submarine launched ballistic missile...

 missile which is currently in active service aboard the Le Triomphant class submarines

Le Triomphant class submarine

The Triomphant class of ballistic missile submarines of the French Navy is the active class of four boats that entered service in 1997, 1999, 2004, and 2010...

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