Suburban Mfg Furnace Combustion Air Housing Cover For Nt Series. It is compatible with Suburban's NT30SP NT34SP and NT40 models. Includes a 90 day limited warranty. Features of Suburban Mfg 390424 Furnace Combustion Air Housing Cover For Nt Series Designed for use with RV furnaces Compatible with Suburban's NT30SP NT34SP and NT40 models Includes one combustion air housing cover per package 90 day limited warranty Package Contents: Suburban Mfg 390424 Furnace Combustion Air Housing Cover For Nt Series Suburban Mfg 390424: Furnace Combustion Air Housing Cover For Nt Series