Comments about Sea & Sea Sea & Sea YS-20A Auto Slave Underwater Flash for MX-5II:
I used my underwater camera with it's internal flash for a few dives and then ordered the YS-20A and immediately got much more defined colorful pictures that were worth keeping and sharing with others. The light from above is mostly filtered out after 20 feet. Even in Hawaii with the bight sun filtering through pictures are much better and no wires to connect. Automatically flashes at the right time effortlessly.
This flash is easy to use.