CPC Subgroup
G07C 1/20 Checking timed patrols, e.g. of watchman
Full Title
Registering, indicating or recording the time of events or elapsed time, e.g. time-recorders for work people (registering or indicating the working of machines or vehicles G07C3/00, G07C5/00) > Checking timed patrols, e.g. of watchman