Honeywell Carbon Pre Filters effectively deodorize the air and trap larger particles such as dust, lint, fibers and pet fur.1 Enjoy the many comforts associated with surrounding yourself with a pristine breathing experience all year round with Honeywell Pre-Filters. Using Honeywell Household Odor & Gas Reducing Universal Pre-filters is also an excellent way to boost and maximize the performance of a HEPA filter. Formulated with activated carbon and zeolite, Honeywell Pre Filter A+ provides extra odor reduction while reducing VOCs. It's a combination that makes these air purifier pre filters excel in reducing household odors such as those from pets, cooking and smoke. Premium odor filters can also be extremely effective in capturing particular household gases such as ammonia and the gases from cleaning products, paint and furnishings.