Convert from microinch to thou

Unit Definition (microinch)
The microinch is a common imperial unit of distance equal to one millionth of an inch, or 25.4 nanometers (nm). The microinch is used for precise machining tolerances and also to describe the roughness of surfaces.

Unit Definition (thou)
An inch is an Imperial unit of length. Sweden also briefly had a "decimal inch" based on the metric system: see below for more.