The HDT IASH II is a versatile heater that is ideal for heating a wide variety of military shelter systems. It provides 180,000 BTU/H (52.7 kW) of clean, heated air from outside your tent or enclosure and can be used on shelters of any size. The IASH II has unparalleled heat control – keeping the interior shelter temperature within 1.5°F (0.8°C) of the setting – providing maximum comfort in extreme climates.