ditto above its not mysterious clear coat !! its clear coat like the rest of the car , i have redone 3 sets of wheels this way , ( i build allot of cars ) any paint stripper will do how ever , aftermarket wheels seem to not have as strong of clear coat as some factory wheels , ive had to resort to bead blasting the rest off on a set of corvette wheels because many coats of stripper didnt fully remove all the clear coat , when you DO get it all off , then re- clear coat . a note here its a double edge sword , the wheels need to have a small amount of bite for the new clear coat to stick to , i did this to a set of momo rims and i made the rims look like a mirror before re-clear coating and then it peeled a year later , your shine will come from the clear coat and the rims dont have to be polished like a mirror //// one more note , most rims that look ugly just need this procedure and can look like new again !!