WE take the Nautilus GPS/Radio (made in Canada) almost everyday on our trips way up north to the shark caves. But we have had a lot of floods. You do not have to register them in Cozumel as the local rescue station monitors them all the time and get GPS numbers from them. MY suggestion is open them once when new, check them out then seal them carefully…only to be opened when absolutely needed.
Dave Dillehay
Aldora Divers
Dave Dillehay
Aldora Divers