4" 3 Hour Vertical Mount Fire Door 2661-30X22 past 12 months SD34 - Transition Box Spiral

SD34 - Transition Box Spiral Pipe Grille (DOUBle Deflection)

Blades are parallel to the longest dimension

Lever operated Multi-Shutter Damper

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

Square to round 2" collar with roll formed retention bead

4" 3 Hour Vertical Mount Fire Door 2661-30X22 past 12 months SD34 - Transition Box Spiralh3. Standard Features * 2661 Square or rectangular fire door for vertical mount only. Maximum dimension 60x60. For damper free area chart A click here * 2663 Out of Airstream fire door. Square or rectangular for vertical mount only. Maximum dimension 60w x 52h. For damper free area chart B click here * 2665 Round fire door for vertical mount only. Available 4" thru 52" round. * 3 hour rated * UL and California State Fire Marshall approved * 4 1 4"