The Voltaic Backpack is built tough for use as a weekend hike bag or as a large daypack. There are pockets & wire channels for multiple electronic devices & 1, 850 cubic inches of storage space. 4 watts of solar power for fast charging The solar panels protect fragile items inside Included battery pack which stores power until you need it 11 adaptors for easy connection to handheld electronics Fully padded laptop sleeve for up to a 17" laptop (16.5" x 11" x 3" or 42cm x 28cm x 7cm) Wire channels throughout the bag for headphones, bladder tubes etc. Adjustable phone / MP3 pouch on the shoulder Removable waist strap High density padding in the shoulder straps & back Mesh backing material for better air flow Shell uses 600D fabric made from recycled PET (soda bottles), which is tough, water resistant & light weight Note: It is not designed to charge laptops, it will however charge cell phones, sat phones, PDAs, GPSs, iPods, cameras & most other handheld electronics