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what are the three small dials on the stopwatch for?

If I'm understandign you correctly they're just different modes you can select.

One is a 60 second timer one is a 30 second timer. Hard press on the face gets you to select different types of modes - analog digital graph hybrid.
 
If asking about the analog screen it is minutes, seconds, 1/10 seconds.

IMG_1333_zpsvhc9nrf0.jpg
 
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