IRULU IPX4 Waterproof Portable Bluetooth Speaker Wireless Outdoor/Shower Speaker Yellow Dual Mode: Bluetooth Mode and SD Card Mode: you can choose to play your music through your Smartphone by connecting the Bluetooth, or insert SD card in the card slot to choose the SD Card Mode Built-in Li-Ion rechargeable battery for up to 10 hours of playback time and built-in microphone for a hands free speakerphone experience. Lower power consumption, Longer Play time, and Reduce power consumption by More Than 80%. Up to 100 Hours of Standby Time Features surprisingly loud volume range with bass feature. Support one button Bluetooth reconnection.