Nikonos III + 35/2.5 + original neckstrap, lubed o-rings, bucket dunked. One of our favorite model as it's full mechanical (no electronics) which makes less opportunity for issues. It has a unique core that is removed from body to load film, unlike traditional rear film door. The 35/2.5 Nikkor lens shoots great in & out of water. It's distance focusing which you don't see in your viewfinder. You select your distance & aperture with knobs on lens, shutter speed on top dial. The Nikonos III has the same features as the Nikonos II. Minor changes is a slightly larger rectangular body, counter on top plate & metal film rewind lever. These cameras are rugged & durable but need care when opening. You should also soak the camera moving all dials & knobs in a tub of water after each usage, along with checking o-ring & clearing off any sand. Keeping them o-rings lubes will prolong the life of them.
Taken from Wikipedia:
The Nikonos III underwater camera from Nikon succeeded the Nikonos II in 1975. This version added a bright-line viewfinder as well sprocket-gear frame spacing (which had been missing from prior Nikonos models). This would be the final model derived from the original French Calypso design inspired by Jacques-Yves Cousteau, although with a slight increase in body size. Its purely mechanical design gives it a reputation for robust reliability.
The standard lens is a Nikkor 35mm f/2.5 with zone focusing and a useful depth of field scale. The version available alongside the Nikonos III has its aperture knob anodized black. Water's higher refractive index affects the behavior of optics: when submerged, the 35/2.5 yields a field of view equivalent to a ~47mm lens on land. The protective planar glass front of the f/2.5 lens permits its use both above and below the surface, which is not true of some of the more specialized underwater-Nikkor lenses.
Camera will be shipped via USPS Priority Mail Flat Rate Box with insurance. Typically takes 3-5 business days & includes tracking. Local shipments have been taking 1 business day!