The only difference we can tell between the original Yashica Pentamatic ’35’ and the Pentamatic II (which came out in August 1960), is the standard lens that came with the camera body.
The original Pentamatic came with the Auto-Yashinon, f/1.8, 5.5cm semi (fully?) automatic 6 element lens. Of course it has the unique Pentamatic bayonet mount and not the M42 screw mount. The Pentamatic II came with the Auto-Yashinon, f/1.7, 5.8cm lens (pictured below). The f/1.8 lens was made for Yashica by Tomioka Optical of Tokyo. New evidence uncovered by us (Oct 2017) indicates that the f/1.7 lens was made by Zunow Optical. It’s a beautiful lens and weighs a ton and is rather rare today at under 6,000 lenses made. It has 10 aperture blades.
Update July 2017 – The Pentamatic II was only for sale in the Japanese home market and for only a short time (Aug 1960 to Jan 1961). Less than 6,000 cameras were made and of course about the same amount of these lenses. No English language sales brochures have been found that mention or feature the Pentamatic II. No advertisements either in English language newspapers or magazines.

The Auto Yashinon f/ 1.7, 5.8cm lens mounted on a later model Pentamatic S.
If you find a sales brochure or advertisement in English that features the Yashica Pentamatic II, please bring it to our attention. Thanks!
Chris & Carol