Alternative Whole of House Water Filtration Unit. It is preferred that this unit be installed after the first hose tap at the front of your home. (If this is not possible, a bypass system may be required - please email us for detail and price.) This will save wasting your cartridges on watering the garden, hosing the verandah, washing the car, etc. This unit comes with a 20" Sediment Cartridge, a 20" Refillable Carbon Cartridge, two of Silver Cannisters - Large size (Before and After unit), brackets, screws and a housing spanner. This unit uses the 'Alternative' sanitisation medium.