Standard construction : Frame: 8"x11/4"x16ga. galvanized steel channel with comer braces. Flange: Corner 0.4" dia. x 8 EA for installation bolt holes. Blades: 6" width 16ga. galvanized steel. Approx 6" on center. Linkage: Concealed in frame or face linkage inside of air stream. Bearings: sleeve bearing Axles: 1/2" dia. galvanized steel. MIN. Damper size: PB single blade-5" W x 4" H, OB-8" W x 14" H MAX. Section size: 48" x 72" MAX. damper size: unlimited. Hand quadrant: for manual operation Steel construction: welded constructions Axles: bolted to blade and tag welded. Finish: Galvanized steel zinc plated hardware. Installation instruction Air flow rate control between Duct and Duct bolt conection Variations(at extra charge) 1. Special finish 2. Special material: alum., stainless steel, etc. 3. Special blade seals and axle shaft seals 4. Special thickness of blade or frame.
