THIS^
First time I forgot so we bought theirs. They are very nice ones. But all subsequent trips we take our own (and some of us still have the ones we bought there). The snorkel areas are full of rough and sharp coral so I wouldn't get in without them. Even my kids who hate them, still wear them there.
They provide wet suit or vest, snorkel (you keep) and goggles. BUT you may bring your own mask & goggles too. My DS brings his own because it is nicer with water stopper at top ... theirs are simple ones with open top.
Only thing you are required to use is the wet suit or vest, at all times in the water. AND you can only use their sun lotion. It is fish safe.