The most secure way to transport goods in checked bags is to fly with a checked firearm. You are required to lock a firearm in a hard-sided case with locks that only you have the keys to -- TSA approved locks are not allowed. You are allowed to lock whatever else you want in these cases too. They are screened more closely and if they can&#x27;t determine contents with an x-ray they will ask you to open the locks in their presence. It&#x27;s a tradeoff for convenience, for sure, but it&#x27;s the only way to travel with securely locked baggage.