Progressive Miners of America
The Progressive Miners of America (PMA, renamed the Progressive Mine Workers of America, PMWA, in 1938) was a coal miners' union organized in 1932 in Gillespie, Illinois. It was formed in response to a 1932 contract proposal negotiated by United Mine Workers President John L. Lewis, which reduced wages from a previous rate of $6.10 per day to $5.00 per day.
Source: Wikipedia — Progressive Miners of America (CC BY-SA 4.0)