General watch waterproof specifications are divided into the following categories: 30 meters, 50 meters, 100 meters, 300 meters, 500 meters.
30 meters: refers to the general life waterproof, is the water when you wash your hands when the water droplets, as there is a light rain falling raindrops, but note can not be too long, not in the sauna.
50 m: no difference between 30 meters and meters, you can ignore.
100 meter: you can take him to wash the car, but not to soak in the water.
300 m: can be used for swimming, but only for shallow swimming. (don't understand for the 300 meters.)
500 meters: this level can dive into the water, if I'm not mistaken is 1, 200 or so like, may also, but don't according to the established value to do so may that watches you can withstand the limit, so don't use this method a test table performance.
Last Don't waterproof to a depth of understanding in the water depth and pressure in all truth is right, but other is wrong, and these are for steel, plastics, rubber strap watch, if leather strap don't leave him even is an ounce of water, including your sweat!