Before diving, the water resistance
The water resistance is measured in bars (unit of pressure, 1 bar is equivalent to 1 atmosphere), as well as watches are tested at this pressure for a certain period. Exceptional pressure, such as when swimming in, so if you're an avid divers have a clock that tolerate these conditions.
Manufacturers often measure water resistance of a number of feet, meters or atmospheres (ATM). As a rule, the fact that the clock in an elastic that (atmospheric pressure) in the depths yet. In general, the following guidelines:
3 ATM (30 m or 100 m): the rain, gentle splash
5 ATM (50 meters or 165 feet): Swimming, splashing in the pool, but no serious jumping or diving
10 ATM (100 meters or 330 feet) minimum requirements for diving
20 atm and greater immersion