Salt spray environment mainly refers to the application environment of medical device connector, electric vehicle connector and underwater application equipment. Under normal conditions, salt spray environment refers to the salt fog environment formed by 5% salt solution. Usually, this environment can effectively evaluate the equipment or components directly exposed to the sea or land salt and other environment, it is not a real environment. The normal exposure time is between 48 hours and 96 hours. Salt spray test is usually used in underwater environment and is usually used to evaluate the corrosion resistance of metal connector shell (e.g. to verify the corrosion protection effect of nickel coating on the surface of zinc alloy die castings). The performance of exposed parts can be confirmed by checking DWV and insulation resistance to determine that the shell seal is effective. Salt spray test is sometimes used to evaluate car connectors. When the car or truck is running, the location of these plate-to-plate connectors may come into contact with water splashed on tires. Especially after snow falls in northern winter, salt will be applied on roads to accelerate snow melting. These connectors are generally subjected to salt spray test to verify their corrosion resistance. The standard of verification is also to check the reliability of contact resistance, not to evaluate by inspection of appearance. Most of the time, these connectors are used with sealing rings to improve their salt spray resistance.