A rod is a unit of length used in some systems of measurement, primarily in the United States and the United Kingdom. In the U.S. customary system, one rod is equal to 16.5 feet or 5.0292 meters. It is also equivalent to 1/4 of a chain, which is another traditional unit of length.
Rods were historically used for land measurement, particularly in surveying and real estate. In some cases, you may still come across the use of rods in property descriptions, especially in rural or agricultural areas. However, the use of the rod as a standard unit of measurement has become less common in favor of more standardized systems like the metric system or the U.S. customary system based on feet and yards.
Millimeter (mm): The millimeter is equal to one one-thousandth of a meter (0.001 meters). It is frequently used for very precise measurements, such as the thickness of paper or the diameter of small objects.