The Gas and Odor Reducing Air Purifier B Pre-Filter - 2 Pack deodorizes the air and helps reduce odors and VOCs using activated carbon and zeolite. Using this pre-filter in conjunction with your HEPA filter, helps your air purifier to capture larger airborne particles such as dust, lint, fibers & pet fur. This filter is compatible with the following air purifier models: HHT-055 / HHT-155 / HHT-080 / HHT-081 / HHT-085 / HHT-090 / HHT-100 / HHT-145 / HHT-149 / HPA-050 / HPA-150 / HPA245 / HPA249 / HPA248 Series, HPA600 Series, HPA160 Series. For best performance, use only Genuine Honeywell air purifier filters and replace every 3 months. In the Box: 1 B+ Pre-Filter (1-pack), Dimensions: 20" x 4.2" x .25"