Manufactured by Synchronome dated 1958 (GPO batch sample date 26 Jan 1959) with functioning working door key. The unit is designed to take 30 second pulse from a master clock, and give a output once an hour and once every 24 hours to operate and re-set telephone exchange equipment.

In the past I have had this clock working and my own clock system, and this clock proved reliable. Will probably require clean and oil before putting back in to use.

Please see photos for actual condition, as these form part of the description. The clock case has usual age related marks.