Filter A: MOLECULAR SIEVE AND ACTIVATED CARBONThe right choice when you need to get breathable air. Molecular sieve removes moisture in the air, and activated carbon removes odors and any oil residue. Filter D: ACTIVATED CARBONActivated carbon is used to remove odors and oil residues. Activated carbon is sensitive to moisture, so to obtain breathable air, it is necessary to use activated carbon together with molecular sieve to remove moisture. CAUTION:The activated carbon-only cartridge should be used when there isnoneed to obtain breathable air. Reviews There are no reviews yet. Be the first to review “Coltri Maxifilter Air Filter Cartridge for ERGO and SMART” Cancel replyYour email address will not be published. Required fields are marked *Your rating * Rate… Perfect Good Average Not that bad Very poor Your review *Name * Email * Save my name, email, and website in this browser for the next time I comment.