Convert from werst to hair's breadth

Unit Definition (werst)
The werst is a German spelling, sometimes seen in English as well, for a Russian distance unit, the verst.

Unit Definition (hair's breadth)
The hair's breadth is a common informal unit of distance. Human hairs vary considerably in width, depending on age, color, genetics, and other factors. An average hair is approximately 70 to 100 micrometers (µm) in diameter, so, as a rough standard, a hair's breadth is 100 µm or 0.1 millimeter (mm).