An international rating system that defines the degree of product protection against solids and liquids.
The first digit indicates dustproof performance and the second digit indicates waterproof performance. The larger the number, the stronger the degree of protection. The degree of protection that each number indicates is as follows:

First digit Second digit
Rating Protection against solids Protection against liquids
Rating 0 No protection provided. No protection provided.
Rating 1 Protection against solids greater than 50 mm. Protection against water drops falling vertically.
Rating 2 Protection against solids greater than 12.5 mm. Protects against water drops falling at a maximum angle of 15 degrees.
Rating 3 Protection against solids greater than 2.5 mm. Protection against water drops sprayed at a maximum angle of 60 degrees.
Rating 4 Protection against solids greater than 1 mm. Protection against water drops sprayed in all directions, at a 360-degree angle.
Rating 5 Protect against dust. Protection against low-pressure water streams sprayed in all directions, at a 360-degree angle.
Rating 6 Perfect protection against dust. Protection against high-pressure water streams sprayed in all directions, at a 360-degree angle.
Rating 7 Protection under water at a depth of 15 cm to 1 m.
Rating 8 Protection under water at a depth of 1 m or more.