About this detail of the Tiger
German tanks had sockets for pluggable electric devices, typically using 12V DC. They used a standard plug/socket combination that was common in European vehicles at the time.
The components conform to DIN 72591 (ISO 4165) and were still in use long after the war. This is a 21st century version of the socket. The plug has two concentric contacts.
The socket could be fixed to a circuit board or a panel. The wiring entered the socket from below. This example (at the left) is in a Tiger.
These are the dimensions of the socket version that is typical of Panzers. The basic dimensions, such as the 46mm between screws, are defined in the DIN standard.
If it was not desirable to bring the wiring through the underlying panel, a cylindrical base could be added, with the socket screws holding both parts to the panel.
It was not a good idea to make holes in armour plate, not even screw holes, so in that case an additional round base would be welded to the armour. The other two items would be screwed to that.
This is the size of the combined base parts.