To avoid scale deposits on the dishes and in the dishwasher, dishes must be washed with soft water. Finish Special Salt effectively softens your water to boost the cleaning performance of your detergent by preventing spots and watermarks on your dishes. Finish Special Salt is guaranteed free from residues. Its purity ensures that your dishwasher's built-in water softening unit works effectively. Other salts may contain impurities like iron and carbonates which could damage the water softening unit.