Question: 1 thou is equal to how many mil?
Answer: Equal to ​1⁄1000 of an inch, it is normally referred to as a thou, a thousandth, or (particularly in the United States) a mil. The plural of thou is also thou (thus one hundredth of an inch is "10 thou"), while the plural of mil is mils (thus "10 mils"). Thou is pronounced like /ˈθaʊ/, not like /ˈðaʊ/.