2-PACK Replacement Filters for Duracraft Humidifier AC-813 / DH830 / DH832 Aftermarket wick Filters fit DH830, Also Robitussin DH832 HC832, AC-813) 2 filters per box. With antimicrobial agent! Measures approximately 4 x 6 x 1 1/2. For optimum performance replace filter twice a season.