Lightly used Nupouch. Adjustable strap. The zipper on the main compartment can be clipped closed, preventing someone from easily unzipping your bag and stealing your things. There's a USB port outside of the pack so you can charge your phone while using it. Place a portable power bank (not included) inside of the pack and connect it to the cable in the bag. Now you can plug your phone to the external port and charge without opening your bag.