Many people think that it is difficult to use chronograph. But it is not so difficult.
Choronopebble is a simple chronograph with slide rule. Chronograph (stopwatch) has automatic tachymeter, it will free us from turning watch bezel. The slide rule has some preset mode like [inch] to [cm], it makes easy to convert units. Chronopebble assists you to use chronograph and slide rule.
Chronopebble has 3 mode. Select button changes the mode.
Calc mode can move bezel to calculate. Press Up / Down button to turn bezel.
Preset mode can convert units. Press Up / Down button to change preset unit.
Stopwatch mode can use stopwatch and tachymeter. Press Down button to start, and press it again to stop. When it stops, bezel turns tachymeter automatically.