The K1 and K3 series "compact" cylinder vacuum was launched in 2002, designed to offer domestic homes with a smaller version of the C series. Using a four layer filtration 3 litre dust bag, (also with the bag door forming part of the underside of the machine) and similar Hospital grade filter system developed on the C series, the K series was also awarded with the British Allergy Foundation seal of approval and carried on with the AirBelt Clean Air diffuser design. Unlike the C series, the K series has only 3 swivel castors. The K is designed to be space efficient and smaller than the C series. Initially fitted with an 1800 watt motor to compete in the market with rivals and featured a new 500gram lighter tube and hose system earned design awards for this model. Also equipped with a longer domestic market hose and 6 metres of cable length, the K series remains popular.