Volume Damper Low-Leak OBD 3000-0BDLL-36X36 Residential Registers & Grilles 904 - Double Deflection Adjustable

904 - Double Deflection Adjustable Aluminum Blade Grille For a 20" x 8" Duct Opening  (front blades parallel to shortest dimension)

53% free area * 1306: 3/4" lattice opening

Standard Features * 1/2" x 1/2" x 1/2" aluminum lattice face *

T-20 Tamper Proof Screws

Volume Damper Low-Leak OBD 3000-0BDLL-36X36 Residential Registers & Grilles 904 - Double Deflection Adjustableh3. Standard Features * Opposed blade operation for precise volume control * 16 gauge galvanized channel frame * Blades are vee stiffened 16 gauge galvanized for strength and stability * Blades pivot on non metallic celcon bushings * 1 2" square zinc plated steel pivot pins * 1 2" square zinc plated steel adjustable operating shaft extending up to 4" beyond the air control frame * Single blades on dampers with a height of 12" or less * Mill finish h3.