As correctly pointed out by ASimpson, there are classification of fits which are application specific. He lists the metric version, imperial are equivalents noting 1.0 inch = 25.4 mm. There are several good references on this, look to the web. But the Machinist Handbook does discuss this, at least in the 23rd edition.
How does Dhea work? DHEA is a parent hormone produced by the adrenal glands near the kidneys and in the liver. In men, DHEA is also secreted by the testes. It is changed in the body to a hormone called androstenedione. Androstenedione is then changed into the major male and female hormones.
However, there have been other studies which do not suggest that DHEA works any better than a placebo pill. In one year-long study, 93 women with low desire were randomly assigned to take a sugar pill or DHEA 50 mg (five times more DHEA than the current study).his is a level found in young, ovulating women. Surprisingly, no undue stimulation of the lining of the uterus has been found in studies where menopausal women were given DHEA 25 mg or 50 mg. However, the women were followed for only 12 months.