Model 3800 watchmans clock
The 3800 is a quartz watchmans patrol clock or watchmans clock, that has a special plastic security case using soft protect covers as additional protection against shock. A wide adjustable shoulder strap makes it comfortable to carry the clock. Two new features include a self closing keyhole for dirt and dust protection, as well as a special hammer mechanism to prevent the watchmans clock from stopping when under duress.
Operation
The watchmans patrol clock is activated by simply inserting and turning a numbered station key which prints information on a carbon paper roll. The imprint shows the hours and minutes as well as the day from 1-31 and the number of the station key.
Unauthorised opening of the watchmans patrol clock is documented. If the 
watchmans clock is opened or closed an additional mark beside the key imprint (K) is printed by the security device onto the paper roll. Its not possible to open the watchmans patrol clock with a station key. Approximately 2000 prints can be made on a paper roll. Imprints of one or more guard tours can be easily torn from the roll or the watchmans clock by authorised security personnel.