602R6 DucTite® Register Box w/Snap Rail Flange conforms to 2009 IRC M601.4.1 which requires joints and seams to be ''Substantially Airtight''. #602R6 DucTite® Register Boxes are insulated at the plant with a true R-6 DucTite® Insulator of EPS. DucTite® is a registered trademark of M&M Manufacturing Company
Standard/Approvals: UL Classified