uv2021

On the Nikonos 5 system the orange o rings were for storage.The black for diving.Don't know about the RS though.

Try contacting helix cameras in Chicago.They have sold underwater applications for years and have lots of knowledge.They are also in Chicago wich would ship in north america no problem.Good luck up there.Should be fun.

Go to sothern-nikonos.com.All the info you need and then some.Print it all off and take it with you when you are away.