Dundas Jafine’s black jacket insulated connector is a listed and marked UL 181 and cUL 181 class 1 air connector.  This connector is ideal for use in general ventilation applications including heating, air conditioning, intake and exhaust.  The Insulated connector helps to reduce heat and cool loss as well as condensation build up that can occur in non-insulated ducts.  Features include a polyester core and black polyethylene jacket.  This connector is offered in R insulation factor of 4.2.