IP, or "Ingress Protection" codes, refer to how well an enclosure is sealed against foreign particles and moisture. They’re expressed by the letters “IP” followed by two numbers, such as "IP68." The first number represents how well a case is protected against solid particles like dust and dirt, while the second protects against water and other liquids. The higher each number, the better the protection. However, it’s important to note that the scale typically maxes out at IP68, which means a case is dust-tight and offers a minimum of protection against immersion in 1 meter of water for up to 30 minutes. This means that the level of protection provided by IP68 cases and enclosures can vary greatly, so always check the specific protection levels offered by each case.