I have actually just had this questions brought up in my league. One of the guys contacted the USBC and found out:
You can use only cleaner that is USBC sanctioned. The back of the bottle will say if it is or isn't.
ALSO, you can alter the surface of your ball. You cannot add surface, but you can take it away (you cannot dull but you can polish). However, at Nationals you cannot do that and also the league president can make a rule that you can't.
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Greg Townsend
Best Bowling Pro Shop, Inc.
Lindenwood University Bowling