Convert from hair's breadth to point [Britain, US]

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).

Unit Definition (point [Britain, US])
The unit of measure for the height of type, defined as 1/72 of an inch* or 0.3527777778 mm (*small differences occur in this unit between countries, the variables lying between 0.188 and 0.4mm)