This Bluetooth speaker comes with a high-capacity lithium battery for extended use before recharging. The design makes it shockproof, dustproof, and waterproof, so it is great for use outdoors. An aluminum alloy carabiner makes it convenient to hang or attach anywhere you want. The effective waterproof level of IPX4 lets you enjoy music and podcasts in the bath or shower. You can also use it as a speaker phone to make or take calls as long as it's connected to your Smartphone. Specifications: Input: DC 5V/1A. Built-in 350mAh Polymer battery, rechargeable. Speaker power: 1W. Product size: 120 53 x 30mm / 4.72" x 2.09" x 1.18". Net weight: 138g/4.86OZ. Working distance: 15-20m. Signal-to-noise ratio: Greater than 75db. Frequency: 200HZ -20KHZ