Product Description TM-1 Takagi Mobius Tankless Water Heater - Natural Gas A unique feature of the MOBIUS TM-1 is its flexibility in large use applications such as big homes, hotels and motels, apartments and other commercial structures. Up to 20 units can be linked together using a single main control system. The use of MOBIUS units allows the building owners to customize the water heating system by using the correct number of units to meet the building's hot water needs. When you are using a MOBIUS multi-system, you don't have to burn a million BTU for one application - just burn as much as you need. Wall mounting brackets are factory included with this model. This model uses Natural Gas. It is also available in LPG (Liquid Propane Gas), lead time may vary Accessories included: Watts 3L150 - Pressure Relief Valve Takagi Mobius TM-1 Technical Specifications