Increase & maintain the longevity of your steam generator&8217;s boiler with Polti's Kalstop Limescale Prevention phials. The product itself is organic, non-toxic & biodegradable that will prevent limescale build up & improve steam emission of your iron, ensuring you achieve professional ironing results at home continuously. The use of Kalstop Limescale Prevention phials also helps steam flow better & keeps appliances running efficiently.