Mount: M42 Auto/Manual
Build quality: good-ok
Filter thread: 62mm
Infrared Mark: yes
Don't let the silver paint fool you, this is actually a rather good lens.
It might look cheap with its aged silver paint, but check what it can do. Becomes an almost perfect "normal" lens with 42mm. (There is some discussion as to what the "real" standard lens should be. The most common seems to be comparing the diagonal field of view across the frame with the fov of our eyes, for 135 = 35mm film this would be around a focal length of 43mm.)
Interestingly, the shot with 2.8 aperture seems a bit too dark. I reshot the test and the result was the same. I used aperture priority for all these shots. The lens is slower than my Tokina 28mm 2.0, but seems sharper and with less distortion.
For some boring brick wall test images, look here.