I used that duplicolor liner stuff on my back bumper after some old lady hit it in a parking lot and cracked a bunch of paint off it. all i did was scour the bumper realy good so the paint had something to stick to. It looks great and has lasted since Feb. This past weekend I went and painted the dulling hitch tubes that were visible so it looked better for a wedding i had to attend. If you use it make sure not to get to much paint in one spot cause it globs up then.