Exameter (Em): An exameter is equal to one quintillion (10^18) meters. This unit is used in astrophysics when describing astronomical distances or sizes.
In the United States surveying system, a "link" is a unit of length that is equal to 1/100th of a chain. Each link is approximately 7.92 inches long or about 0.201168 meters. This unit is primarily used in surveying and land measurement in the United States.
Surveyors often use a chain, which is comprised of 100 links, to measure distances in land surveys. The use of links and chains allows for precise measurements of land parcels, boundaries, and property lines.