Comparable to Air Purifier HEPA & Activated Carbon -PUR131 Replacement FilterFilter replacement kit includes one (1) HEPA Filter and one (1) Charcoal based Activated Carbon Pre-filter for Air Purifier -PUR131, Part -PUR131-RF.Captures 99.97% of airborne allergens and contaminants as small as 0.3 microns including pet dander, mold spores, pollen, smoke and dust from the air.Replacing the Air Filters To replace your the air filters in your -PUR131 air purifier follow the steps below:1) With the air purifier off, unplug the air purifier and remove the back cover2) Remove the old air filters and properly dispose of them3) Unwrap the new air filters. Place the Activated Carbon filter inside the housing first, making sure the pull tabs are facing the opening4) Install the True HEPA filter into the housing; make sure the pull tabs are facing the opening.5) Replace the back cover onto the housing6) Plug in and turn on the air purifier. Use a pen or a pencil to press the black reset button inside the vent on the side of the air purifier. The ""Change Filter"" symbol should now be off Be sure to also clean the dust sensor on the side of the air purifier using a clean cotton swab When Should I Replace My Filters,The air filters can be used for up to 6 months, depending on how often your air purifier is used.Premium compatible HEPA filter replacement set for Air Purifier -PUR131colour:Black + whiteMaterial:Plastic + spongePackage Contents:1 * HEPA Filter1 * Activated Carbon Pre FilterOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.