Alen BF35 Air Purifier Filter, 1-Pack, Hepa-Pure RECOMMENDED FOR ~ Allergies, Dust, Pollen & Dander. BUILT FOR YOUR CONCERN ~ Our HEPA-Pure filter offers a high capacity HEPA layer to capture 99% of airborne particles down to 0.3 microns. Also includes a washable mesh prefilter to extend the life of your filter. SINGLE REPLACEMENT ~ Youll receive 1 BreatheSmart Classic HEPA-Pure Filter. Upgrade to a 5-Pack or 10-Pack, and youll receive a savings on your order for buying in bulk. NOTICE! ~ FILTER FIT CHECK ~ This filter fits the BreatheSmart Classic Air Purifier. It does not fit other units in the BreatheSmart series of products. It does not fit BreatheSmart FIT50, BreatheSmart FLEX, BreatheSmart 75i or BreatheSmart 45i. Check your units control panel to determine which BreatheSmart series air purifier you own.