Ultradent 90-second porcelain etch is used to etch porcelain veneers, crowns, bridges, inlays, onlays, and fractured dental porcelain. Features: - Porcelain etch is a viscous, buffered 9% hydrofluoric acid. - Etch is easy to control and place. - Will not stain composite or resin cement. - 1.2 ml syringes.