Pressure Relief Horizontal Air Up 3520-12X18 Step Down Ceiling Diffuser Note: Sizes listed are the

Note: Sizes listed are the duct or opening size the grille will fit into

alternate frame is extruded aluminum with signature line marks

SD52 Series Performance Data

Louvers designed with rolled rib for maximum strength and rigidity

with 75% free area Options 14 GA 304 SS Construction 12 GA (

Pressure Relief Horizontal Air Up 3520-12X18 Step Down Ceiling Diffuser Note: Sizes listed are theh3. 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