RCD Corporation® #9 Mastic® is a low VOC adhesive-sealant used for permanently sealing the fabricated joints and seams of sheet metal air ducts, UL-181 listed rigid fiberglass air ducts, UL-181 listed flexible air ducts and thermal insulation. RCD Corporation® #9 Mastic® is preferred by contractors for new residential and light commercial air duct installations. It is ideal for repairing damaged and leaking air ducts and sealing conditioned spaces from air infiltration. 

#9 Mastic® is more than an air duct sealant - due to its white color, ease of application and ability to adhere to all types of contruction surfaces it is used as a termite monitoring system in buildings with crawl spaces. A 3" or wider stripe of #9 Mastic® around the top of  the perimeter of the crawl space creates an easily monitored zone for detecting termites crossing the barrier to the wooden structure. Easy application by brush, trowel, palm, spray or extrusion.

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Water-based & non-flammable High solids content City of Los Angeles Approval # RR8204 Contains Ceramic Microspheres Low VOC - less than 10 grams/liter Weather Resistant Fire Resistant	Elastomeric Easy application & clean-up Earns LEED Credits
Adheres to most construction surfaces, including but not limited to:
Aluminum Foil Aluminum Foil Scrim Calcium Silicate Insulation Cellular Glass Fiberglass Insulation Galvanized Steel Gypsum board Concrete	Masonry Polystyrene Foam Polyurethane Foam Polyester Plastic Primered Steel PVC Plastic Sheet Aluminum Wood