Compatible with: Krcher A 1000, A 2000, A 3000, A 4000, K 4000, KNT 2, MV 2, MV 3, NT 20/1, NT 27/1, NT 27/1. 1. NT 38. /1, SE 4000, VC 6000, WD 1, WD 2, WD 3. Replacement model 6.414-552.0 / 64145520 (full list of all models listed below)Heavy duty: Hanging filters are used to separate impurities from the vacuum cleaner's exhaust air. It filters fine dust particles with a diameter of up to 40 m (= 0.04 mm), such as dust, smoke particles, bacteria, viruses, pollen, and mites. Certified according to DIN 44956Purpose: Your 1ELEMENT vacuum cleaner maintains 100% suction power thanks to our 1ELEMENT filters. To ensure this, you should replace the filter at least every six months (or more often in homes with children, pets, or smokers). Certified according to DIN 44956EASY TO CLEAN: With our slatted filters, you can vacuum up all dirt, whether wet or dry, without having to change the filter. However, clean the vacuum cleaner filter regularly, check it for damage, and replace it promptly if necessary.