YTR.co Rugged Waterproof Portable Bluetooth Speakers with Hand Free Function and Build in Power Bank with Aux-In YTR.co Rugged Waterproof Portable Bluetooth Speakers with Hand Free Function with Aux-In RICH BASS & HUGE VOLUME - UP TO 8 HOURS OF STREAMING MUSIC: Our Bluetooth wireless speaker delivers rich bass & huge volume in premium quality, high-fidelity audio for all the contemporary beats you love to play for your friends.