Ultimate Sound: The BOOM 4 portable waterproof Bluetooth speaker delivers rich, 360-degree sound and deep, accurate bass, all carefully balanced so you can hear every note Powered for Adventure: This waterproof portable speaker has a rechargeable battery that stays powered, pumping tunes for 15 hours on a single charge A Bluetooth Waterproof Speaker Made for the Outdoors: Rated IPX7 waterproof and drop-proof up to 1.5 metres (15 feet ), the BOOM 4 floating Bluetooth speaker is virtually indestructible Party Up: Use PartyUp on the Ultimate Ears BOOM app to pair several BOOM, MEGABOOM, EVERBOOM, EPICBOOM, and HYPERBOOM portable Bluetooth speakers, creating the ultimate surround sound experience Magic Button: Play, pause, skip, and control music directly from your favourite streaming service; set up one-touch playlists on platforms like Spotify, Amazon Music on Android, or Apple Music on iOS