Seal-B machine brightener for black cars is also a swirl mark remover. It is made with the finest polishing ingredients and special polymers to completely seal the surface to produce an exceptional shine with a great depth of gloss. Seal-B is designed to be used with a high speed buffer and it will stay wet under the buffer head just as long as you like. The longer you buff, the deeper the shine. Unlike most machine brighteners which dry after a few passes. Seal-B does not dry. When you are satisfied the degree shine is what you want, stop buffing. Wipe the car down with a dry towel.