They are just 2nd quality balls, usually because of some sort of cosmetic mistake. They are perfectly legal to use. Like all bowling balls, you should check to see if the CG is accurately marked before drilling the ball.
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The pacifist is as surely a traitor to his country and to humanity as is the most brutal wrongdoer.
--Theodore Roosevelt
"The only difference between a Liberal and a Communist is the Communist knows what he's doing."