The first polyester balls came out in the late fifties, but they really took off around the seventies when they started beng used on the pba.
According to Don Johnson They looked at plastic balls back then , like we look at resin balls today.
Don Johnson talked about how they snapped into the pocket (which shows how much lane conditions have changed today) and Glenn Allison made the comment back then that plastic carried more garbage hits than rubber. Which is basically just what is said today about resin balls.
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