4-Pack Replacement Filter Compatible with IOOO K31, Also Compatible with Aucleia/AIRTOK/KQLKJ KQ-31 Air Purifier, H13 3-in-1 HEPA Filter High-Efficiency Carbon Filter Filtration

3-Stage Filtration High-efficiency Activated carbon Air Clean Dust. | H13 Grade True HEPA Filter, and High Efficiency Activated Carbon Filter | H13 Grade HEPA Filter 99.7% of airborne particles down to 0.3 microns in size,High-Efficiency Activated Carbon, filter All sorts of smells and smoke | Please replace regularly to keep your machine fresh, Replace every 4-6 months depending on the usage and environment | Easy to replace, can be installed without the use of any tools, if any problems with the process, please contact us