Self-generating piezo starter lasts for 20,000 starts. 100% safety shut-off valve prevents non-ignition fuel discharge. Adjustable heat settings. No flame, no flue or chimney, no fan or blower and no noise. Wave Heaters can be used inside an RV as a portable unit (with leg stands) or permanently mounted. Wave Heaters can also be used outdoors as portable units (with optional leg stands, LP cylinder, regulator and hose assembly, all sold separately).