This replacement HEPA air filter is specially designed to keep your DEWALT DC500 Two-Gallon Wet/Dry Vacuum operating at peak efficiency. The commercial-grade, high-efficiency GORE pleated filter captures particles as small as 0.3 microns and will even trap up to 99.97% of ultra-fine drywall dust. The washable filter can be tapped cleaned, or rinsed under running water, and its unique design allows it to be left inside the vacuum regardless of whether you're vacuuming up dry debris or wet spills. There's no need to remove it when sucking up liquids. And it's backed by DeWalt's 90-day money-back guarantee, full one-year service contract, and three-year limited warranty.