Both the black cat and wooden shoe were often used by IWW artists and cartoonists to symbolize "direct action" at the point of production by workers, including (sometimes) sabotage. The word "sabotage" is derived from the French word "sabot" the name for a wooden shoe. These two items would have been produced prior to 1918,  the year the IWW renounced sabotage as a tactic due to the backlash of public opinion. The pin is 1-5/8" wide with enamel on brass "IWW" logo flanked by a pair of metal shoes. The reverse bar is inscribed "Sterling Front". The hatpin is nearly 10" tall, topped by a three-dimensional metal shoe 7/8" wide. Likely, a male member of the IWW wore the pin while his wife used the hatpin. The only examples we've seen. Typical and trivial tarnish, otherwise essentially Mint. Ted Watts Collection.