Try Bostik QuartzLock 2 premixed grout in your installations for a better quality grout and a quicker install. QuartzLock 2 is a premixed grout that can be used on horizontal, vertical, interior, or exterior, surfaces. Bostik premixed grout is resistant to most food stains and many residential chemical products. QuartzLock 2 is semi-flexible, strong grout with great adhesion principles, making it an excellent choice for a wide range of applications. Bostik urethane grout can be used on natural stone, ceramic, glass, or porcelain tiles. QuartzLock 2 comes in over 20 different colors. Available in 9lb or 18lb buckets.