Spiral Flame Gas Patio Heater 40,000 BTU. Spiral Flame Propane Heater is a functional work of art adding warmth and modern style to your backyard. Encased in a tempered-glass tube, watch the spiral flame dance up, as up to 40,000 BTUs of heat to keep you warm. The powder coated bronze shell is durable and works with any decor style. Included wheels allow for easy mobility while the emitter screen and reflector cap help spread the heat. Accessible parts may be very hot. Do not move the appliance during use. Before start-up, first read through the safety information and the operating manual carefully. Only by doing so will you be able to use all of the functions safely and reliably. Keep the operating manual and pass it on to any third party that might own the heater after you.