MU-408 PowerPool is an instant grout filler mortar specifically designed for submerged areas such as swimming pools, ground water tanks and outdoor areas. Contains SmartShield Plus which strengthens the grout against water pressure and exposure to chemical agents, maintains color longer and makes the grout less prone to rust. cracks and is able to inhibit the growth of fungus.Suitable for installing mosaics, natural stone (wide grout), ceramics and granite tiles.