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Grainger US Acklands Grainger

Designed to be used with specific Dayton Bath and Ceiling Ventilators to function as a heat barrier and to protect fire rated ceilings. Intended to stop the spread of heat and flames through the building's ventilation system and to protect both the fan and the ductwork. UL 555 Classified, rated at 3 to 4 hours fire resistance. 165ºF fusible link included.