Surround yourself in sound now with stereo linking, the Swimmer Duo gives you more robust sound and a better sonic range. Easily link two together and listen to each one as true surround sound. With IPX7 waterproof rating, the Swimmer Duo can be immersed in up to 3 feet of water for 30 minutes. The speaker is also dirtproof and shockproof. The flexible tail can be wrapped around any object. Plus the tail can be removed and replaced with a suction cup use in the shower or any flat surface. The average playback time is 8hrs. It takes 2hrs to charge the speaker from 0 to 100%.