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Sea to Summit says:
The Cardkey TSA Lock is a lightweight lock with cable, which uses credit card and key ring sized keycards to keep in your wallet or with your travel documents.
With airport security increasing, we want you to arrive at your destination with your luggage locked and secure. Avoid having your padlocks cut off or worse, your zip sliders cut off by using our padlocks which are Travel Sentry® approved and feature the Red Diamond, alerting the TSA and other airport security agencies that they can open these locks without destroying them.