Brass-O does a really good job of shining up plastic. However, it can ONLY be used on UNPAINTED portions of the toy. Be careful not to get any on the paint...because Brass-O will remove it. I discovered that it shined up the plastic real nice one night while trying to remove the stripes on Alternators Wheeljack. I believe what it does is fill in the minor scratches in the plastic...similar to the stuff you can get for real cars...but I could be absolutely wrong.