There are also two bushings on the movable sheave ,one around the helix and one around the shaft.If you can find a good Cat roller secondary cheap this is the better way to go.I installed one on my prox600 and the dif is much better also cheaper than an after market roller just as good.This is the only thing that I will own that says Cat on it and since Polarises roller sucks I don't no about the new team performance roller, I will use the Cat secondary .