What is IP68?
IP stands for Ingress Protection, 6 means Dust Tight, meaning that no dust can go in easily. The last character, 8, means it is water resistant tested with depth more than 1m. Some mobile phones like Apple iPhone 11 will specify the depth and the duration tested. If you see IP67, with 7 as the last digit, it means the device had been tested with up to 1m depth with usually up to 30 minutes.
*Performed by professional, please do not try this at home.