The video depicts a triple expansion steam engine in operation on the Liberty ship Jeremiah O'Brien in San Francisco. The scenes have been taken during March 2019.

Liberty ships were a class of cargo ships built in the United States during World War II in large numbers. The Ships were propelled with a 140ton vertical triple expansion compound steam engine. The engine's design was obsolete, but the engines were easy to build in high numbers by the many shipyards engaged in the construction of the Liberty ships. The engines were rugged, simple and easy to maintain. The engines are 21 feet (6.4 m) long and 19 feet (5.8 m) tall. It operated at 76 rpm and could propel a Liberty ship at about 11 knots.

The Liberty ship Jeremiah O'Brien is one of a few ships still existing still in operating conditions. It is based in San Francisco.