The M4 is also a motorway in Sydney, Australia, running from the western suburb of Emu Plains to the inner western suburb of Strathfield.
The M4 is also a motorway in the Republic of Ireland, running from the west of Dublin to Kilcock. it is being extended to west of Kinnegad, where the route becomes the N4 and continues to Sligo.
The M4 Medium Tank is the formal designation of the Sherman tank.
The M4 missile is the intercountinental thermo-nuclear missile carried by the French Redoutable class submarines. It is capable of more than 4500 km strikes.