The JBL Tune 520BT headphones transmit the powerful JBL Pure Bass sound thanks to the latest 5.3 BT technology. These very easy-to-use headphones offer up to 57 hours of pure listening pleasure and 3 additional hours of battery life with only 5 minutes of charging. Download the free JBL Headphones app and customize your sound through the equalizer, the voice prompts will help you know the performance of the headphones. Manage calls, sound and volume from the headset, all with the convenient button control. If you receive a call while you are watching a video on another device, the JBL Tune 520BT headphones easily connect to your mobile so you never miss a call. The JBL Tune 520BT headphones are light and comfortable even after hours of listening, and you can fold them to take them in your backpack everywhere.