External USB with built-in charging cable, Anti-theft design. And this bag do not include a battery, you need a power bank to charge it. Size: 7.9" x 4" x 12.2" The sling pack can fit a laptop up to 7.9''. The bag can be either carried with the hand handle or adjustable shoulder strap. Designed for Comfort: Made of water repellent nylon fabric, light-weight ,No more aching neck, back & shoulders like with a backpack! Ergonomically designed, padded, breathable strap makes you forget you're even wearing this bag. Ultra-comfortable across your back and chest. It can act as a single-shoulder bag/sling bag, or a cross-body bag for use.