Product: Accord ABBBWH15 Baseboard Register with Sunburst Design, 15-Inch(Duct Opening Measurement), White
Brand: Accord Ventilation
Color: White
Steel construction
For floor application, 2-3/4-in projection
180˚ air deflection with a volume control damper
Removable faceplate for easy installation and cleaning
Actual length of item is 15-inches; inside duct opening measurement of item is 12-inches to accommodate the 1 ½-inch wide flanges on each end

Search query: 18 in baseboard diffuser
Relevance: Substitute