NG-SS AZ Patio Heaters Outdoor Natural Gas Patio Heater in Stainless Steel The impressive Natural Gas Stainless Steel Heater with integrated ignition features heavy-duty design and enough heat to warm even the chilliest evenings. This easy-to-use natural gas heater puts you in control of the temperature. Capable of reaching 41 000 BTUs it can keep an area 10 feet in diameter toasty warm for hours. For your added safety the patio heater also features thermocouple and anti-tilt safety devices; CSA approved.