Calculated Industries 6414 - Manual (Page 14)

To use the Metric Measuring Mode, press [Set] then [Reset]
and [Units] together. The DigiRoller will measure in Metric
units until you press these keys again.
Turning the Bell On/Off
The DigiRoller/DigiRoller Plus has a built-in bell sound, which
you can turn on or off. The bell is only heard when you are
using the Count/Auto Count functions. To turn the bell on or
off, press the following two keys simultaneously:
[RESET]-
[Rcl]. Note that you may have trouble hearing the bell in
noisy outdoor settings.
12 – DigiRoller/DigiRoller Plus ™