You have an almost new III? Terrific...enjoy!!!
The Nikonos is a marvel, and I got onto using them in 1979 when I bought a III for backpacking and climbing (I do not dive). Years later I got onto the idea of collecting the I,II, and III models with one caveat: they must be new or near new. Why? Because 99% of all Nikonos cameras see terrific use in the hands of those who dive or want a quality adventure camera. So that was the challenge: find examples as perfect as posdsible when that goes against the grain (it is actually easier to find a black Nikon SP in mint condition, but tougher to purchase). I have succeeded in getting new and near new I, II, and III models and use a second III for outdoor rough stuff trips. My favorite is the II. FYI: I have tons of shades, replacement seal kits, lube, flashes, etc. as I really got into Nikons stuff 10 years ago. They still fascinate me, and I am very glad I have them to use and behold. Now I'd like an original Calypso, the camera designed in part by Cousteau that was the camera Nikon bought the rights to in 1960 to create the Nikonos brand.
Darn: now you know the roots of my RFF user name. Oh well...