The Off Grid Voltaic Backpack is built tough for use as a weekend hike bag or as a large daypack. There are pockets and wire channels for multiple electronic devices and 1500 cubic inches (25 liters) of storage space. 
The OffGrid Solar Backpack is a versatile bag. The solar pocket is removable and can be attached to other bags or anything else as it charges. 
Electronics: The electronics are the same as the other Voltaic solar bags. Note: It is not designed to charge laptops, it will, however, charge cell phones, sat phones, PDAs, GPSs, iPods, cameras etc.
Power: 4 Watts total peak output at 6 or 12 Volts (selectable depending on charging application)
Charge times: 4-5 hours in the sun will fully charge a typical phone, 1 hour will provide about 3 hours of talk time.

Universal USB Battery stores power for use anytime and is specially designed to charge efficiently from solar. When not in the sun, the battery can be charged using the USB Power Cable or optional AC travel charger or DC car charger making it just as useful on the grid as off. Charge times: Battery will be fully charged from 7 hours of direct sun, 5.5 hours from USB port on laptop or optional DC or AC * Capacity: 3,000mAh, 11 Watt hour capacity Output: 5.5V, 600mA via USB port Input: 4.8-12V, 650 mA Connect to Devices via the USB Port or 5 standard adapters Bag Specifications Detachable Charging Section: Solar charging section zips off and can be attached to another bag, bike rack, etc. with the included straps and clips Volume: 1500 cubic inches (25 liters) Dimensions: 18" high x 12"wide x 8" deep (46cm high x 30cm wide x 21cm deep) Weight: 4.5 lbs (2050 grams) including battery and solar panels Padded laptop pocket: Dedicated pocket fits up to a 17" laptop Wire channels: placed throughout the bag for headphones, bladder tubes etc. Phone pouch: Sits on the shoulder strap and allows you to charge with easy phone access Removable waist strap Built for Comfort: High-density padding in the shoulder straps and back. Mesh backing material for better air flow Fabric: 600D shell made from recycled PET (soda bottles), which is waterproof, lightweight and UV resistant