I came across a few Mil. spec. 500k rev log pots. for doing a proper Ernie Ball speed pedal conversion.The original pot in the phase 100 was a 500k rev audio log.This pot is nearly impossible to find in a Claristat or Allen Bradley J style pot it is even harder to fin in a long shaft version so it can be used in the E. Ball vol. pedal. The problem with using the 250k in the pedal is that the sweep makes adjustment very hard w/ the pedal. i have three of them i had to make a company minimum of $100. They are $25 + shipping. Or if you want to send me your Ernie Ball I'll do the convert for you for $40 + the pot.