Silent, small & mobile, but with the same convincing suction performance as ATTIX 50. A perfect solution for craftsmen on the move. Operating costs are minimized with the washable PET Fleece filter elements, & the low working noise level lets you work when others are nearby, without disturbing them. The excellent design offers you cable storage, accessorie storage & a big tool deposit to keep all you need at h&. While dealing with fine dust the Push& Clean Filter cleaning system offers a comfortable & quick way to clean the filter. The 21 model features an automatic on/off system which is designed for people who use the machine with electric hand tools, as starting or stopping the tool also starts & stops the vacuum.