Purchase and installation of AprilAire #600 Humidifier, AprilAire #2200 or #2400 Air Cleaners, AND Air Scrubber Plus required for additional savings. Valid at participating locations. Not valid for HSP, third party, new construction customers, with any other offers or discounts, or prior sales. Coupon required at time of service. See service center for details. Void if copied or transferred and where prohibited. Any other use may constitute fraud. Cash value $.001.