Black Rain Proof Bike Mp3 Audio Speaker Outdoor Sport Bicycle Mount Sound System Model R801 High-textured aluminum alloy surface, stylish and classic design. Built-in Hi-Fi high-quality and high-efficiency speaker monomer, with clear and loud voice. Built-in high-capacity rechargeable battery, it can support overlong time play. With the function of music player & Line IN, it is easy to handle. With TF card slot, it can plug in TF card to play the music as you like.