Even when you use distilled water in your iron in everyday use, calcium is deposited in the fine steam jets. This special iron descaler cleans these deposits professionally. Prym supplies it in child-safe ampoules, each containing 14 ml. All the odour-free organic acid mixture is poured into the reservoir of the iron and filled up with distilled water. After ironing out the residue on an old cloth, repeat the process with the distilled water twice or three times.