About this item Wide Compatible: Universal compatibility with Android and iPhone tablets, smartphones, iPods, MP3, MP4, and other Bluetooth enabled digital speaker players. Built-in Battery: This speaker features a built-in rechargeable battery. Charge the battery fully before your first use and only use the supplied USB cable to charge the speaker. Built-in Microphone: Equipped with a built-in mic and hands-free function, you can conveniently take calls with this mini speaker when connected to your smartphone, whether at home, in the car, or in the office. Impressive, User-Friendly Design: The detachable suction cup and aluminum alloy metal hook provide convenience for hanging and attaching it anywhere. It is designed to withstand harsh environments, as it is dustproof and waterproof. Portable Speakers: Enjoy high-definition stereo sound with impressive volume, perfect for lounging, partying, walking, camping, hiking, or biking. Dimensions: 3.6 x 3.2 x 2 inches.