Reproduction brass portable sundial, which allows the user to orientate the device to tell local time anywhere from the equator to 60-70 N/S latitude ( good luck any higher than that!).
The compass bezel is 3.75”, the box is 5.5” square and 2.6” deep.
It’s a fascinating little piece, which comes in a neat mahogany box (lining has peeled and been lost).