Padlock and Chain or Cable

This combination is essential, especially for solo travelers. The lock is needed for lockers in hostels, and, with the cable, can be used to secure your pack to train luggage racks, another pack, etc. Those old reliable Master combination padlocks from junior high are perfect. Avoid keys for obvious reasons. For the cable, try to get something at least 48 inches long and a quarter-inch thick, or the same length of solid chain. The cables sold at bike shops that are curled up like a slinky and coated with plastic are perfect. If your hostel or pension doesn’t have any lockers, chaining your pack to a bed, pipe, or other solid object, by the shoulder straps, is a good idea. Obviously, a determined thief could cut the straps, but that would leave him with a ruined, awkward-to-carry backpack. Really, you’re just trying to deter the opportunistic thief, or at least make him pick somebody else’s bag.