The 1927 Plus Four Wristlet Route Indicator's tiny interchangeable paper maps seem quaint compared with their modern counterparts

And this one was made in Britain.

The device is thought to be the first navigation device for motorists, without being built into the car itself.

Worn like a wrist-watch, it is loaded with a tiny paper road map that is rolled across the face by adjusting two small black knobs.
It comes with set route maps, such as London to Bournemouth and London to Edinburgh, and the driver winds the knobs to move the map on as their car travels further.