Pressure Relief Horizontal Air Up 3520-24X20 Smoke-Fire Damper inner dimension and outside dimension

inner dimension and outside dimension available * Available in continuous lengths with butt joints * Tamper proof screws * Standard Color

Standard Features * Removable core * Available in five air patterns * 22 gauge steel flush core provides uniform air distribution * Square to round No Labor Collar (6" thru 18") * 2x2 galvaneal steel panel with seismic support holes * Soft White Options * 700DVD D - steel multi-shutter damper * 700DVD O - opposed blade damper * 700DVD FR - U

102 - two way

Standard Features * 2533 - Square or rectangular for vertical mount only

Extruded aluminum frame with signature line marks

Pressure Relief Horizontal Air Up 3520-24X20 Smoke-Fire Damper inner dimension and outside dimensionh3. Standard Features * 3510 Vertical mount * 3520 Horizontal mount air up * 3530 Horizontal mount air down * Designed to open with negative or positive pressures for intake or exhaust air * Felt edge blades to hold noise to a minimum * Aluminum construction * Blade to blade linkage * 1 4" pivot pins in nylon busings * Maximum size 24 x 24 * Mill finish h3. Options * Sleeve variations * Mounting flange * Adjustable counter balance to adjust various