Appearance size: 77*39.5*77mm Maximum output power: 5W Bluetooth version: V5.1 Effective distance: within 10 meters Battery charging time: 3 hours (5V/1.0A input) Battery type: Rechargeable carp battery Music playback time: 4 hours Battery capacity: 400mAh Connectivity TechnologyUSB Recommended Uses For Productoutdoor Controller TypeBattery Powered 1. Small Size But Loud VolumeWith a 5W high performance driver and passive subwoofer, the mini Bluetooth speaker releases a richer, louder and deeper sound without distortion. 2. Unique Camera Look The small speaker has a classic appearance. It features a square design and blends modern technology with classic style, combined with advanced digital audio technology. Just like taking you back to the days of camera, enjoying a relaxing moment in todays busy life. 3. Portable Lanyard DesignThe small wireless speaker is portable. A special choice for both leisure time and formal occasions! You can always have it with you, day or night. Just enjoy your life with this innovative mini portable speaker! 4. Bluetooth 5.1 & Long Battery Life Equipped with advanced Bluetooth technology, this portable Bluetooth speaker can connect with your smart devices quickly and smoothly. With a built-in 400mAh rechargeable battery, this mini speaker can play for up to 4 hours at 50% volume.