An HVAC duct sealing system has an air duct wall, a sealing surface, such as an HVAC case, against which the air duct wall is biased, and a seal member interposed between the duct wall and the sealing surface. The seal member is interposed between the air duct wall and the sealing surface and is molded directly onto the air duct wall using a two-shot or double shot method of forming. The seal can be rubber or any flexible, pliable material capable of creating a seal with a surface. The seal has a seal base that is attached to and surrounds an end part and two sides of the air duct wall. The seal has a flexible tip portion extending from the seal base that is biased against and bends against the sealing surface in accordance with an amount of pressing force to create a seal. The flexible tip bends between 0 and 100 degrees from its pre-installation position.