This product is the Calmag CalMag Magnetic Scale Inhibitor 15mm SI-CALMAG. The CalMag magnetic scale inhibitor is suitable for installation on cold water lines for the prevention of limescale formation. The unit is supplied as standard with 15mm compression fittings. The CalMag unit can also be adapted for use with push-fit fittings. No earth bonding is required. Any scale that has formed around taps, sinks, showers, etc, will begin softening with regular contact with treated water. This soft scale is easier to remove than normal hard scale. Surfaces frequently in contact with treated water are easier to clean - shower heads are also descaled. After several months of descaling, hot water system efficiency will gradually increase.