General purpose scaler-timer, suitable for radioactivity counting utilising a GM tube and as a general purpose millisecond digital timing device with manual or electronic triggering. 6-digit, bright green LED display. Manual or timed counting of 1,10 or 100 seconds. Press-to-read switch to read the accurate applied voltage to the GM tube. Auto ranging on timing modes. Built in loudspeaker and switch on the back of the machine allows audible indication of counts when required.