Stylish and powerful, the Montero Speaker allows eight hours of uninterrupted play on a single charge of its built-in lithium battery. The aux input enables you to hook up the Montero to your existing stereo setup, or you can transmit wirelessly using the built-in Bluetooth receiver. And just in case your phone battery is running low, there’s also a built-in USB charger to keep the music going as long as you like.