Tumi Luggage Lock
Because of the price I'm almost putting these on here as a joke, but they really are the perfect lock. Why did everyone stop making these? You only want clip locks just like this, trust me! You can keep them clipped on your luggage even when they're unlocked. You don't set them down while you're getting into your bag, you can leave them on as a deterrent, great for your daypack, etc.
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