What a useful travelling companion. Instead of trying to remember a tricky number, use a favourite word to set the padlock combination. During flight delays, you could even improvise a word game to pass the time. These are also TSA (Travel Sentry Approved), which means when travelling to the US the airport authorities can open your Padlock with a special key. If you lock your suitcase with a non-TSA Padlock the authorities will almost certainly cut your padlock open and open your suitcase.