Pressure Relief Horizontal Air Up 3520-24X10 Smoke-Fire Damper T-Bar hinged 2 Cone Step

T-Bar hinged 2 Cone Step Down Diffuser with Round Collar

stair risers

inner dimension and outer dimension sizes available * Tamper proof screws * Standard Color

904 Series Performance Data

904 - Double Deflection Adjustable Aluminum Blade Grille For a 18" x 4" Duct Opening (front blades parallel to shortest dimension)

Pressure Relief Horizontal Air Up 3520-24X10 Smoke-Fire Damper T-Bar hinged 2 Cone Steph3. 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