Quiet Cool Classic Diagram ADJUSTABLE HANGING STRAP o Keyhole straps that allow you to adjust, up or'down, without removing the screw so the fan can be hung in nearly every attic space. HIGH-PERFORMANCE ACOUSTICAL DUCTING e Noels dampening technology with insulated ducting that is used to separate the steel housing from the living space. DUCT CLASP © Duct clasp that helps secures the ducting to the Airtight Damper Box and Steel Housing without screws or tape.