Watchman's Tell tale Clock by Flonic type BG101

Metal. Case size approx 4.5" diam. x 2.5" high

"Detect 101" High quality 8 day clockwork movement with lever escapement, 11 jewels and elinvar hairspring.

A special numbered key is kept at each point on a watchmans round . This is inserted and turned to print the key number and the time. There is a mechanism to detect fraudulent interference

An excellent example complete with strong leather case, a station key and the manufacturers leaflet.