Genuine Austin Air Pre-filter replacement. Choose the Right Filter for Your Model. Replace every other year when using air purifier 12 or more hours a day.
Common Manufacturer Model Numbers for this product are as follows:
Austin Air Prefilter
Important Note: Due to electrical certifications (CSA & UL) all units state HM400 or HM200 on the label on the underside of the unit\'s casing/body. This is a certification that pertains to the electrical portion of the unit.
All the bodies of the units are the same.
This is not to be confused with the filter configurations which allow the unit to be specifically made for various niches such as pets or chemicals. It is this filter design that makes a unit an HM402 Bedroom Machine, HM405 Allergy, HM410 Pet Machine, HM450 Healthmate Plus, and HM400 Healthmate, etc...
The same is true for the HM200 series (ie the Junior series).