Long lasting up to 12 months The Philips NanoProtect HEPA Series 3 filter features an efficient pleat design with 111 pleats, covering an area of approximately 1.6 m², ensuring a long service life of up to 24 months. Captures 99.97% of particles The Philips NanoProtect HEPA Series 3 filter is made from high-quality materials and can capture particles as small as 0.3 microns, which includes common airborne allergens, harmful particles, bacteria, and the most common viruses. It captures up to 99.97%. The high-quality filter, with its strong and stable structure, ensures that all air flows through the filter, providing highly efficient filtration.