Honeywell Home Whole-House Humidifier and Humidistat furnace duct-mounted model HE280A. Suitable for homes up to 4,000 sq ft. Features bypass duct mount for cleaner operation and compatibility with all furnaces. Designed to humidify homes typically over 2,000 sq ft and up to 4,000 sq ft for newer or remodeled homes. Utilizes water-saving technology to use less water than standard models. Ideal for adding or replacing an existing humidifier, installations with access to a floor drain, or installations with full access to air ducts. Actual unit size: 16.25" x 18.5" x 9.75".