Many brands of watches are marked in the instructions for use or guarantee statement: waterproof 30 m, only wash splash;

Waterproof to 100 meters, for swimming or snorkeling;

Waterproof 200 meters, water dive.

Many people wonder, when activity can be used to buy water when you watch, why recommend waterproof watches over 100 meters. "

I'll never dive more than 50 meters ", a diving coach so I said.

In fact, this question not only general consumers who buy watches, a few years ago most of the watches sold and repaired master table is not care about this problem until recently Sport Watches market attention, began to pay attention to waterproof marked difference, but I do not know why.

Whenever the water depth increases under ten meters, will increase the pressure equal to atmospheric pressure.

In accordance with this principle, tab stops are generally based on pressure gauge to test the performance of waterproof watches.

So the compression tab to indicate the value.