Do NOT use TSA locks on your gun case. This is a misunderstood area of the law and, technically speaking, it’s illegal for you to do so. Per the letter of the law, as discussed in the footnotes of this article, you alone must maintain possession of the keys or combination to open your gun case. You cannot lock it in such a way that others have access. By using TSA locks on your gun case, lots of people, just about anyone in fact, technically has access to your guns. TSA locks are NOT secure and not even TSA agents are supposed to have access to your case, once cleared, without you being present to unlock the case.
http://blog.beretta.com/10-gun-tips-you-need-to-know-about-flying-with-guns
§1540.111 Carriage of weapons, explosives, and incendiaries by individuals.
Sorry for the confusion. TSA lock on my suitcase, padlock on my gun case opened only by me.