The Power Base was introduced in 2008 and has used 3 different oulleys sicne that time
The first pulley was a large white plastic pulley that used a 3/16" dia. belt. These thinner belts were black and then later changed to orange.
By 2010 we changed the motor to a higher torque model and this necessitated the use of wider belts measuring 1/4" in diamater. These belts were originally Clear but later changed to Orange. The key issue with these belts is that they are 1/4" in diamater. When this change occurred we also changed to a metal pulley on the Power Base. This metal pulley was never used with the older 3/16" belts. So the easiest way to determine the type of belts that you need is by simply looking at the pulley on the Power Base. If it is metal, then are using 1/4" belts (orange or clear - either will work).
The picture above also shows a White Plastic pulley that was used on the Power base for about 1 month in 2014 or so. This pulley eventually would fail in the area of the set screw. The set screw would loosen up and could not be retightened.
If you have a White pulley on your Power Base and you are using 1/4" Belts, then contact us for a free pulley replacement. We will send you a metal pulley. Caution if you are using a white plastic pulley and your belts are the older 3/16" type then you do not need this replacement (at least not yet, but you will when you upgrade the motor in which case the replacement motor that you will purchase will include both this pulley as well as a new Ball Winder pulley with the correct groove diameter). In every other respect, both of these pulleys look alike.