The LZOS Jupiter-9 85mm f2 is a telephoto lens for the M42 thread mount. Smooth focusing, good diaphragm, no fungus. There are some minor internal cleaning marks, but these do not have an effect on the imaging, which islovely: this is a classic Zeiss design, and while it wont be tack-sharp wide open, it sure looks pretty. Extra bonus: this lens is no larger than the average 50mm (though it is heavier)