The Comfort Glow 12,000 BTU Natural Gas Vent-Free Heaters are a reliable and efficient natural gas heaters for indoor use that heat up to 400 sq. ft. Using radiant infrared technology, this heater warms people and objects directly with heat generated from two durable ceramic plaques—delivering comfortable, sun-like warmth. Designed for convenience and dependability, this unit operates without electricity, making it an excellent choice for backup heat during power outages or use in off-grid environments. The manual control knob allows you to easily turn the heater on and off and adjust heat output to your preference. With 99.9% fuel efficiency, this vent-free heater requires no chimney or external vent, offering flexible installation options. Built-in safety features include an Oxygen Depletion Sensor (ODS), Safe Watch pilot system, and over-pressure protection allowing for indoor operation. The compact design (20" H x 17.3" W x 9.1" D) comes ready for wall mounting. An optional floor mounting kit (ASIN: B00S04XHC6) is available but sold separately for added versatility. A compatible blower (ASIN: B00S04X79O) can also be purchased separately and added to enhance heat circulation (requires 120V outlet). Fits all Kozy World and Comfort Glow Infrared models above 10,000 BTU's and produced in 2015 or later. Specifications: Heating Capacity: Up to 400 sq ft Fuel Source: Natural Gas (NG) Power Settings: 12,000 BTUs Safety Features: Safe watch pilot / ODS system, over pressure safety device Special Features: No electricity required, 99.9% fuel efficient, electronic ignition, manual heat control, 2 plaques Dimensions: 20"H x 17.3"W x 9.1"D Warranty: 2 years WARNING - CALIFORNIA RESIDENTS ONLY: This product and the fuel used to operate this product (natural gas), and the products of combustion of such fuel, can expose you to chemicals including benzene, which is known to the State of California to cause cancer and reproductive harm. For more information go to: www.P65Warnings.ca.gov