The ProCom Heating Infrared MA Series of Vent Free Heaters delivers reliable heat and offers an easy way to add an extra heating source to your home. The heater has an easy push-button start with no electricity required, making it a great choice during power outages. The manual heat settings allows you to maintain and control the desired heat output, while the oxygen depletion sensor features an automatic shut-off design to keep your home safe. Please Note: This Item Is Not for Sale To Residents In California. Check your local regulations before purchasing and installation. Vent-Free heaters do not operate at elevations above 4,500 feet altitude. Installation and service must be performed by a qualified installer, service agency or the gas supplier.