Ericsson field telephone
This is Ericsson field phone used by the Swedish Army. It has selection for local battery and central battery systems. Also it has extra receiver. I did not find serial number from this, so I cant not say when it is produced.
On top there is text "Fiende lyssnar" which means that the enemy is lisning. User instruction says that new battery type will be taken to use in 1.1.1955.