The Allerair 4000 DS air purifiers feature a unique tar-trapping pre-filter that grabs larger particles and tar, which also extends the life of the HEPA filter.
The unit features a micro-wrap filter to deal with small particles as small as the fine cigarette ash and a 3" extra-deep 16 lb carbon bed which increases dwell time, allowing more chemicals, gases and odors to be absorbed.
The only proven to work method of adsorbing lingering substances that result from smoking tobacco in a closed environment long after active tobacco has ceased.