#6 Mastic® - 1 gallon pail#6 Mastic® - 1 gallon pail
#6 Mastic® - 1 gallon pail
#6 Mastic® - 2 gallon pail
#6 Mastic® Caulk Tube
#6 Mastic® Duct Joint

  • Fiber Reinforced
  • UL Listed
  • Weather Resistant
  • Earns LEED Credits
  • Water Borne
  • Non-Flammable
  • Low Odor
  • Made in U.S.A.

#6 Mastic® Fibered Air Duct Sealant

RCD Corporation® #6 Mastic® Low to High Velocity Air Duct Sealant is a fiber reinforced, water-borne, white, UL listed, flexible, sealant used to permanently seal the joints and seams of flexible air ducts, ductboard (rigid fiberglass air duct), sheet metal air ducts, thermal insulation, crawl space vapor retarder, house wrap, and UL listed air ducts. #6 Mastic® seals leaks in return air ducts, supply ducts, air handlers, plenums, grilles, registers, dampers, and boots and is used in home sealing to reduce air infiltration into the living area. Sealing the home from air infiltration, sealing air ducts and crawl space sealing improves indoor air quality, reduces humidity, improves indoor comfort and saves energy. Color is white and is easily applied by brush, trowel, palm, extrusion, or spray equipment. #6 Mastic® Low to High Velocity Air Duct Sealant is preferred by professional HVAC and home weatherization contractors nation wide.

RCD Corporation Technical Bulletin lists spray and extrusion equipment solutions.

  • Mastic 1
  • Mastic 2
  • Mastic 3
  • Mastic 4
  • Mastic 5
  • Mastic 6

Please note: To order quantities greater than available through RCD’s online store please contact us at 352.589.0099 or send an email to customercare@rcdcorp.com and we will be happy to fulfill your order.