Product details:

But even with their small size and amp draw, these gas furnaces are capable of heating sizeable living areas quickly and efficiently, with capacities from 16,000 to 19,000 BTUH. NT-SE models are direct discharge furnaces with attractive grilles for zone heating of smaller RVs, trailers, truck campers and even pop-ups. A side duct on SE models is optional. NT-S models can be ducted to provide even heat distribution throughout the coach. Q = Quiet, Operational difference is quieter and lower amp draw. Direct Discharge 19,000 BTU/H Electric Ignition Vent Assembly INCLUDED Black Grille is INCLUDED 22 LBS Cut Out Dimensions: 10 9/16" Wide x 10 3/16" High