Al Capone cars

Reading the latest edition of Classic Trains, Fall 2008, I noticed on page 45 a picture of a train which consisted, apart from the locos, on “a string of Al Capone” cars.

What were the Al Capone cars and why did they get that sobriquet? Were they something only to be found on the RI or did other railroads have them?

The so-called “Al Capone” cars were open-platform suburban coaches that operated on the Rock Island into the mid-1970’s. The name came from the fact that they were built in the 1920’s.

I have come across this Museum. It shows the cars very well.

http://www.mtmuseum.org/jsr/roster/crip2608.php