Mystic Wonders Duck Tape Magnets take randomly unorganized molecules and turn them into smaller more organized molecules. When a liquid passes through the field of a polarized magnetic field, a natural reduction in molecular size and alignment occurs, causing a synergistic effect. This smaller, organized molecule is capable of greater solvency, causing their penetrating properties to increase. The Duck Tape Magnets will work on plastic, steel and copper lines. Good for shower heads, too. Lasts a life time, once in place. (set of 2) Magnetic water conditioning using the technology of magneto hydrodynamics reduces tension, hinders growth of hard scale and helps remove existing scale.