Product: Dampers Dampers Underground Preinsulated Duct System Cable Operated Dampers Cable Operated Damper Assemblies ITEM#SizePDFDWG 08-0071(1) 08-2560 + 8" [203 mm] Damper 10-0071(1) 10-2560 + 10" [254 mm] Damper 12-0071(1) 12-2560 + 12" [305 mm] Damper 14-0071(1) 14-2560 + 14" [356 mm] Damper