This is another area where I don’t economize. Go to a good athletic supply store, and get the best mask and snorkel you can find, preferably in day-glo colors so that boaters can’t miss you in the water. (Those of you who need a prescription mask can order one through your optometrist.) Fins are simply un-packable, so if you really need them, pick up an inexpensive pair in the islands. Online, in the US, www.DiversDirect.com is a good place to browse.