GOOD / This is a USED camera. There are signs of age and use, small dent on the top above the serial number. The filter has some small marks but I do not think it will impact your images significantly.
The Mamiya 16 Automatic is a subminiature viewfinder camera taking 10x14mm images on 16mm film. It was made in Japan by Mamiya, introduced in August 1959. It has a collapsible optical miniature viewfinder and a built-in selenium meter combined with an analog calculator for exposure settings that is coupled to the aperture. Other selectors are the shutter speed thumb-wheel, the film type reminder, the distance setting shifter, and a shifter to set a yellow filter in front of the lens.
Mamiya made a fairly successful series of 16mm cameras for 13 years -- from 1949 to 1962. Their cameras are known for their outstanding features and ease of use. Their downfall was due, in part, to the nemesis of 16mm cameras -- a unique cassette. Actually, Mamiya made a wide variety of cassette styles, but all the types apparently fit in all of their cameras. Some were metal, some plastic. Some were single-lobed, some double-lobed. Some had snap-on caps, some screw-on. Some were designed for re-use, some not. Mamiya also made many cosmetic changes within each particular model. In other words, your Super 16 II probably will not look exactly like your neighbor's Super 16 II. These differences are not well documented, and the various idiosyncratic types are prized by collectors.