Pressure Relief Horizontal Air Up 3520-16X12 past 12 months Curved saddle with gasket provides

Curved saddle with gasket provides airtight fit to spiral pipe

Performance Data With Opposed Blade Damper

available 4" through 40" round (2549)

linkage and handle enclosed in valve to assure trouble-free operation * Countersunk mounting holes for flush appearance with color matching Phillips posi-drive screws * Steel multi-shutter damper * Soft White Options * 200 O - steel lever operated opposed blade damper * Tamper proof screws * Standard Color

Pressure Relief Horizontal Air Up 3520-16X12 past 12 months Curved saddle with gasket providesh3. 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