The 5088 Empire Comfort Systems floor furnace provides ~total comfort~ for a fraction of the cost of electric heat.Needs no electricity to operate Matchless push - button piezo ignition Millivolt wall thermostat Whole - house heating capability Wall thermostat included with all units All parts carry a 3 - year limited warranty Proudly Made In USABottom of Unit for Air: 6 BTU Input: 45,000 Casing Length and Width: 34 x 22 Draft Diverter and Vent Connector: 6 Each Side to Nearest Wall: 6 Floor Opening (Length and Width): 34.32 x 22.32 Height: 25.75 Inlet to Floor: 20.25 Iron Pipe Size (N.P.T.): 0.5 Overall Length (Including Diverter): 43.5 Register Color: Tan Register Length and Width: 36 x 24 Shipping Weight (Two Cartons): 128 Lbs. Size of Flue Collar: 4 Diameter Temperature Control Millivolt Wall Thermostat: Yes Two Adjoining Sides to Walls: 18 Type of Gas (State on Order): Natural or LP Venting Center of Flue to Floor Covering: 18.63 Venting Floor to Top of Diverter Shield: 12.25