Takumar-A 28mm f2.8 prime lens.

Wallace: “A Takumar lens with a Pentax K mount! Well, what do you think about that, Shawn lad?”
Shawn: “........…?”

Wallace asks me to explain it to Shawn using information found on the Internet:

Me: "Takumar lenses with the 42mm screw thread are members of the Royal Blood Line in Pentax lore. The Takumar lenses with the K or bayonet mount are apparently of the lesser nobility. They were produced after the screw mount had been discontinued and as a cheaper alternative to the Pentax branded bayonet lenses which typically had SMC (Super Multi Coated) stamped on them. This particular Takumar A lens clearly has some kind of coating on its elements but it does not boast about it on the lens barrel. Some Takumar lenses were issued with the brand name Cosmlcar and were marked MC for just plain Multi Coating.
On the lens barrel, the markings for f8 on the aperture ring and 10 feet (3 metres) on the distance scale are differentiated by orange ink. The logic seems to be that if you set the aperture to f8 and set the distance scale to 10feet (3 metres) everything from 5 feet (1.5 metres) to infinity will be in focus. All dependent on the film speed/shutter speed and light level of course; but it makes everything sound easy.
A 28mm focal length lens designed for full format/35mm film format cameras converts to 'effective' 42mm on my DSLR (APS-C) camera. The lens lacks autofocus of course, but if I find that I really like this 28mm focal length, I can always buy a Pentax-FA HD 31mm f1.8 Lens for only £1,049 (USD $1452/€1218) more than I paid for the Takumar."

Shawn: “........…?”