Part messenger, part backpack, and part carry on, The Timbuk2 Ace Backpack carries what you need whether you're traveling by plane, bike, or bus. The nylon exterior is reinforced with a durable tarpaulin that will handle everything from pedal commutes to overhead compartment crammings, year after year. After year. A padded tricot lining keeps your goods safe and secure, and an internal 15 inch padded laptop pocket keeps your computer safe from the bumps and tumbles of travel. Wear the Ace as a messenger bag or rig up the tuck away straps when you want to wear it as a backpack. The TSA friendly design makes it an excellent carry on, and the luggage attachment strap lets you piggyback it on rolling luggage. A ventilated mesh back keeps it comfortable when you've got it on as a backpack, and the custom fit straps along with a removable sternum strap let you customize the fit of this ever versatile pack.