A "finger" is a traditional unit of length used for measuring cloth or fabric. Similar to the span, the finger is based on the width of a human finger. It was historically used in various countries, including England.
In England, a finger was typically equal to about 2.25 inches or approximately 5.715 centimeters. However, like other traditional units of measurement, the precise length of a finger could vary depending on the region and historical context.
Micrometer (µm): The micrometer, also known as the micron, is equal to one one-millionth of a meter (0.000001 meters). It is used in scientific research, especially in fields like microscopy and nanotechnology.