A boom chain was/is used to attach the ends of logs together to make a log boom. Log booms were popular in the early years of the Pacific northwest logging when logs were floated to sawmills. The boom contained the logs to prevent them from floating away. This chain is about 6 feet (2 meters) long.

About 3" holes were bored through the logs near the end of each log. Then the T end of the chain was feed through the holes to tie the ends together. This provided a flexible connection that could easily be removed when needed.