BRAVEN Balance Portable Wireless Bluetooth Speaker [18 Hour Playtime][Waterproof] Built-in 4000 mAh Power Bank Charger - Retail Packaging -Black Braven Balance for Bass Optimization. Charge your mobile device using the speaker's built-in 4400mAh Lithium-ion battery. Built-in noise-canceling microphone for hands-free calls. Durable IPX7 certified waterproof rating.