Here is an explanation of what different IP ratings mean for watches. Most watches we sell will be either IP65 or IP66. Some are starting to be IP67 which makes them great for continued use in water.
This table describes the official level of protection provided.
Protected from low-pressure water jets from any direction.
Protected from high-pressure water jets from any direction.
Protected from immersion between 15 centimeters and 1 meter in depth.
Protected from long-term immersion up to a specified pressure.