Yossarian

Howdy gents. Getting ready to go back to old school scheduling w/Puck Boards. What are the actual magnetic pucks that were roughly 3/4" x 2.5" originally called? I'm trying to order the magnetic "????s" and have no clue what to type into the Google. For those born after 1990 these are the pucks that have a slot/lip (sts) on the top/bottom for laminated names to slide in/out of (sts).