In this chain reaction there are 60 big dominos each containing 990 dominoes, and a small field of 600 dominoes (which says 60,000) to bring the total up to 60,000 dominoes used.
The big dominoes span about 14 feet across.
The entire setup goes down in about 12 seconds.
You can view different angles and slower views of the setup here…and fails from the project here.
Watching them come down is a very satisfying experience, for some odd reason.