The carbon Bose SoundLink Mini Bluetooth Speaker II incorporates proprietary technologies and an optimized driver configuration to deliver full-range sound with deep low-frequency reproduction. This speaker pairs with other Bluetooth-enabled devices and allows wireless music streaming up to 30' away. For non-Bluetooth-equipped devices, there is a side-mounted 3.5mm auxiliary audio input. The speaker is also equipped with a built-in rechargeable lithium-ion battery that provides up to ten hours of playtime.The included charging cradle recharges the battery and can act as a base for the speaker. While housed in its cradle, you can charge the speaker as you're listening to music. There are also top-mounted power and volume buttons to control playback. A micro-USB port allows for software updates to ensure ongoing compatibility with your Bluetooth devices. The SoundLink Mini Bluetooth Speaker II features a single-piece aluminum casing for durability and to provide a contemporary look. Weighing in at just 1.5 lb, the speaker allows for easy portability.