Speedi-Collar SC-10 10-Inch Diameter Take Off Start Collar without Damper for Hvac Duct Work Connections Reviewhttp://tinyurl.com/nq46cgf Speedi-Collar SC-10 10-Inch Diameter Take Off Start Collar without Damper for Hvac Duct Work Connections Speedi-Collar is made in the USASaves time, labor, energy, and money with all the innovations Speedi-Collar has to offerThe damper ratchet system allows you to adjust the damper into 6 different positions for optimal balancingSpeedi-Collar features an integral gasket, a �-Inch wide flange and quick-zips for an air-tight connectionSpeedi-Collar is molded from high density, UV resistant resin making it durable, lightweight, dent and rust-proof