Irvin "Zabo" Koszewski (August 20, 1924 – March 29, 2009) was an American professional bodybuilder and a 2007 inductee to the International Federation of BodyBuilders Hall of Fame.

John Balik of Iron Man magazine recalled that "he had a 10-pack of abs when everyone else had a six-pack.

A photograph of Koszewski is included in the iconic Pop Art collage Just what is it that makes today's homes so different, so appealing?

Koszewski died of pneumonia in Doylestown, Pennsylvania at the age of 84.

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