Mechanical counters are used to totalize, detect and indicate the existence of sequences of events in those types of applications that are devoid of an electric power source. There are four different kinds of mechanical product types including rotary counters, pushbutton or manual counters, stroke counters and revolution counters. The rotary counters perform their functions by recording counts a particular number of times per rotation. The pushbutton types are those that are operated manually and involve the operator recording each actuation himself. These manual devices are mostly handheld types. Stroke counters perform their tasks by measuring count strokes in degrees. Finally the revolutionary counters function by recording one count for each time the shaft revolves. Mechanical counters can sometimes be reset using a lock and key and manual knob.