This is a very small 200mm lens, and because of this fact, it was one of the first I went after when collecting small primes for my APS-C collection. It's long and thin, and feels a little weird on a full-frame DSLR. In fact, it looks and feels a little weird on any camera. This is one of the cheapest legacy Pentax I could find. A good copy cost at the time between $50 and $100, and I've seen them go for less. The problem is getting a good copy. Because they were one of the most common M-series lenses, there are many that weren't treated with the proper TLC in the day. Plus, some have internal defects. Truth be told, this is the second copy of this lens I bought. The first introduced me to the concept of delamination: this is when two internal glass elements that are glued together become unglued. This looks like a dirty, hazy ring around the outer edge of the lens. This won't affect the image quality unless the defect is large, however it is progressive, and it is difficult to fix. In my case, the defect was on the small rear element, so I decided to sell the first copy for parts and get another.
Delamination isn't due to maltreatment as might have been alluded to above. It's a spontaneous defect that can occur over time due to weakness in the glue, or environmental conditions in which the lens was stored.
The lens is 405 g (0.9#) and, focused at infinity, 111mm long (4.4 inches) and has 8 aperture blades and 52mm filter threads. The fast aperture of f/4 is on the slow end for lenses of this focal length. The lens bears the usual aperture ring and has a rubberized grip for easy manual focusing. Minimum focus distance is 200cm (6.6 ft) producing 1:7.8 reproduction ratio (0.13x).