This small museum has an excellent collection of all forms of underwater apparatus, scuba dive gear, subs, sensor systems, etc., and showcases items from at least 10 countries.
I liked the history section, where visitors learn how diving (and diving gear) has evolved over the centuries. The presentation on cave diving was also fascinating. Though small, this museum is definitely worth a visit if you're in the Panama City Beach area. There is a small gift shop and a collection of books on diving and the like as well.