Wall heater is NATURAL GAS. It is unvented with thermostat control. Model M30. Max input B.T.U. HR. 32,000. Min input B.T.U. HR. 24,000. Made by Martin Industries. Manual included.Approximate assembled measurements: Depth 9", Height 22", Width 26".Heater is $150.00. Cash only please.Callfor an appointment.Located off Highway 92 in Hiram ..... between Dallas and Douglasville.Thanks for looking.