THE EXPANDABLE BACKPACK TRANSFORMS TO SUIT WHATEVER THE SITUATION REQUIRES. UNZIPPING AN EXTRA 2 INCHES IN DEPTH FOR EVEN MORE STORAGE. I WAS LUCKY TO HAVE ONE ON MY LAST TRIP, AND I PLACED MY COMPUTER AND ALL THE CORDS, MY CAMERAS, EXTRA CLOTHES, MEDS, NOTEBOOKS, AND READING MATERIALS ALL IN THIS BACKPACK. IF YOU ARE LOOKING FOR A BACKPACK TO TRAVEL WITH, PLEASE YOU NEED TO CHECK OUT THIS PROPPER PRODUCT. GO TO www.propper.com/ FOR MORE INFORMATION AND LOOK AT ALL THE WONDERFUL PRODUCTS THEY OFFER TO THE OUTDOOR INDIVIDUAL. I USED MINE AS A CARRY ON BAG AND BOY DID IT WORK WELL FOR ME. IF YOU ARE A HIKER, BIKER, SNOWSHOE USER, SKIER, HUNTER, FISHERMEN, AND TRAPPER, YOU HAVE TO GET THIS BACKPACK. I LOVE MINE AND I WILL BE GETTING ONE FOR MY SON NOW. AS MANY OF YOU KNOW, I USE A SCOOTER TO GET AROUND, AND NOW I FOUND A BACKPACK THAT WILL CARRY EVERY THING I NEED TO ENJOY A DAY IN THE OUTDOORS. IF YOU WANT TO KNOW MORE OF MY USES FOR THIS BACKPACK, EMAIL ME. HAVE A GREAT DAY IN THE OUTDOORS!