Its not your standard 9mm, 16mm, 24mm pot. You need to buy a special "wah" pot generally. They run you around $10 - $30.

Or when you say size do you mean resistance?
OHH when you can't seem to find that baseball thats... on ebay...

ugh horrible comercial reference... sorry

i think
http://www.smallbearelec.com got some too
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