Any of a variety of types of telescopic poles, fitted at the upper end with a brush and water jets, fed either from vehicle-borne tanks of deionised water or by on-site production of deionised water using a domestic or commercial water outlet. The water is filtered by either a two-stage or three-stage filtration process, involving a carbon filter, and two de-ionization filters, or a carbon filter, a reverse osmosis membrane filter, and a de-ionization resin filter. The filtered water contains a TDS (total dissolved solids) of less than 5 ppm. (parts per million.) The brush is used to agitate the debris off the window, while spraying water, and then the brush is lifted a few inches from the glass to rinse the glass with the pure water jets. Fan jets are used for hydrophobic glass, and “pencil” jets are used for hydrophilic glass. The de-ionized water is lacking in ions, so it will pull solids off the glass and dissolve the solids into the water, aiding in the cleaning process. Because there are no solids dissolved in the water, the windows dry clear without water spots. Water-fed poles vary in length. The longest poles are about 70 feet, and can reach up to six storeys. Water-fed cleaning is also referred to as pure water cleaning. It is common in the UK and becoming common in the US