Class 019
Non-Metallic Building Material Products
air-conditioning ducts, not of metal; grilles, not of metal, for ventilation openings; grilles for ventilation openings, non-metallic; grilles, not of metal; ventilating ducts, not of metal; non-metal ventilating ducts; non-metal vent covers for HVAC ducts; non-metal heating ducts; heating ducts, not of metal; vent covers, not of metal, for HVAC ducts; non-metal air-conditioning ducts; ducts, not of metal, for air-conditioning installations; ducts, not of metal, for ventilating and air-conditioning installations; ducts, not of metal, for ventilating installations; ducts, not of metal, other than for electrical circuitry
