Need to touch up painted or discoloured grout? The Ronseal One Coat Grout Pen quickly and easily transforms the surface giving a durable and waterproof finish in one coat. So now there’s no need to re-grout. Colour: Brilliant White.Available in Two Sizes (ml). Areas of use: Interior tiles.Approx. number of coats: 1.Application: Pen.Drying time Approx.: 24 hours.Protection level: Medium.