M-Edge International Backpack with Battery (BPK-B4-PO-B) Patent-pending battery interface on exterior of bag allows for charging and use on-the-go Included battery provides 4000 mAh charging capacity to power your tablet or Smartphone Multiple organizational pockets. Fits laptops up to 17''. 1300 cu. In. Of storage space Battery provides an additional 25 hours of battery life for most smartphones and 8 hours for most tablets Modern design features water-resistant 1200D military-grade nylon and waterproof YKK zippers