Replacement activated carbon pre-filter for enviracaire air cleaners

Replacement activated carbon pre-filter for enviracaire air cleaners Pre-filters should be replaced every three months. Some filters may require replacement sooner depending on particulate build-up, environment and conditions used. Use with Honeywell® Air Purifier``s HWL-18150, HWL-50200, HWL-50250 and HWL-17000. For Quietcare™ & Enviracaire® Air Cleaners & Purifiers Filter Type(s): Activated carbon; Filtration For: NA; Maximum Room Size (W x H): NA; Width: NA.