Compatible with the Dustex 25 L and Dustex 35 L. Replaces conventional fleece filter bags. Reusable. Reduces costs and waste. The permanent filter from Fein replaces fleece filter bags, eliminating the need for repurchasing. It can be used in combination with the Dustex 25 L and Dustex 35 L wet and dry vacuum cleaners. The Fein brand was founded in 1867 by Wilhelm Emil Fein to manufacture physical and electrical devices. His son Emil Fein invented the first electric hand drill in 1895, laying the foundation for the highly reliable power tools that Fein continues to produce in Germany and that are valued worldwide in industry and craftsmanship.