My disposable razor was packed in my shaving kit, which I had packed in my dive bag. They went through ALL of my bags with a fine-tooth comb. They took it out of my shaving kit to confiscate it.
I'll admit, it's a crapshoot going through security in COZ, but I don't believe it's worth the gamble. And, besides that, they aren't allowed in Cozumel anyway, so leave it at home.
How long ago was that? Whenever it was, you simply got unlucky with a very poorly informed security screener who didn't understand the difference in a checked bag and a carry-on...and I have to assume that was on your way out of the country? There is no customs law that prohibits personal grooming items including a disposable razor. I come back with dozens of them at a time because the ones I like can't be bought here.
To answer the OP's question...this is Cozumel...a primarily diving related destination. The customs people (even in Cancun) are quite familiar with diving equipment, including dive knives...and there is no law that prohibits bringing these items with you, in your checked bags.
AS far as my comments about bringing in it carry-on luggage, it was a general statement, highlighting the fact that carry-on bags are the ones you have to worry about, not checked bags.
However, as has been stated at least half a dozen times by the veterans (who you solicited advice from) knives are not allowed within the marine park
(which includes 99.9% of the divable sites in Cozumel - soon to include Playa del Carmen and that strip) so you had your answer two pages ago. And if that wasn't a good enough answer, you've had just as many people say they've brought their knife with no problem, but don't use it.
nmdiveboy:
Okay, my question may have been poorly punctuated, but I KNOW for a fact, I didn't ask about the marine park.
If you asked about diving in Cozumel, then yes you did.
So choose the answer you like the best...and don't solicit advice from the veterans if you don't like what we have to say! For an inexperienced diver that was just certified last month, you can learn a lot from these very helpful and knowledgeable veterans...so be nice!