With its world-leading 97% energy efficiency, the future is now with the Glow Brand™ T180. The only system of its kind on the market, the Glow T180 holds 1-gallon of hot water inside the unit itself, within dual stainless-steel tube heat exchangers. The flexible unit mounts on the wall and takes up about the same area as a 200-amp electrical panel, with the option to set the unit to either Comfort Mode (95°F) or Eco-Mode (86°F) for additional energy savings.