Kenn, I don't know the answer to your first question. I built my track cleaning car about 10 years ago and don't even know if there were other choices then. I know now there are several different choices, even some with foam on one side. You don't want those. Mine are green and have some kind of white printing painted diagonally across the pads. I bought the brown Trackman pads at York when they were still in business and had a booth there also several years ago. They are both very durable so I have never needed any more.
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Dennis