Designed to fight back against the build up of hard water, Calgon has a unique formulation with active ingredients which soften hard water, preventing limescale from forming. A preventative rather than a descaler, the earlier you begin using Calgon Expressball tablets in your washing machine, the better. Recommended by many leading washing machine brands, each individually wrapped tablet contains an expressball which actively protects against limescale and dirt residue, helping your machine to work better for longer. Contains 75 tablets.