Computers; Microphones; Batteries, electric; Battery chargers; Cables, electric; Divers' masks; Scuba diving masks; Sound transmitting apparatus; Apparatus for transmitting and reproducing sound or images; Transmitters of electronic signals; Ultrasonic sensors; Face masks for diving; Underwater dive computers; Pressure sensors; Downloadable computer software for scuba diving, free diving, and snorkeling, namely, for providing alerts based on dive time and depth, recording locations, monitoring tissue loading and ascent rate, sharing medical information, sharing photos and videos related to dives; Underwater intelligent display devices, namely project key data such as diving depth, duration, and gas cylinder remaining on the diving mirror in real time. Combined with underwater communication technology, information transmission between the device and the diver is achieved; Scuba diving equipment, namely, rebreather oxygen controllers, rebreather oxygen sensor monitors and dive computers