Walkie Talkie, Transceiver, Two-Way Radio. This product is the first and only Snorkeling Communication Unit availableit is an exclusive Patented technology by OCEAN REEF. Rechargeable Battery Via USB Rated IP68. These practical transceivers make communication possible while snorkeling Four different channels are used in pairs for direct one on one communications or for group narration by snorkeling tour leaders Long-life battery for continuous use assured for several hours Communication can only occur while the unit is above the water Range 150 mt (500 ft) any drection (doesnt work underwater) Complies with different countries rules ( FSR for USA, PMR446 for EU) 4 different channel for separate conversations Any number of Snorkie Talkie can comunicate with each other on the same channel Rated IP68 (waterproof 3 mt/10 ft) Battery level indication 8 hrs operating time 1200 hrs stand by battery life Adjustable volume Also compatible with other standard radios.