One of the largest prison strikes in U.S. history is happening right now.
SEE MORE: Prisoners Stage One Of The Largest Strikes In U.S. History
Prisoners in at least 13 facilities are on strike to protest "prison slavery."
They're also protesting working conditions and other labor grievances.
U.S. inmates work in prison. Some studies have shown prison job programs help inmates get a job after being incarcerated. But on average, they make less than $1 an hour. (The federal minimum wage is $7.25.)
You may have bought products made with prison labor.
Walmart, Starbucks, Microsoft and Victoria's Secret are just some of the major companies that have used prison labor.
Last year, Whole Foods announced it would stop selling food produced in prison.
The striking inmates are calling on other prisoners to join them: "To every prisoner in every state and federal institution across this land, we call on you to stop being a slave."