A-A-52545 Heaters, Vehicular Compartment 28 Volt, DcThis CID covers two types of heaters of 28 volt (V) direct current (dc) nominal rating, used for heating crew and engine compartments of military vehicles or equipment. Type I heaters are intended for use on military vehicles or equipment which may be required to operate in an ambient temperature to minus 65 degrees Fahrenheit (-65 Degrees F); from which a supply of gasoline is available; when heated air is required without the vehicle engine being operated. Type II heaters are intended for use on military vehicles or equipment from which a supply of heated circulating liquid (engine coolant) is available, which may be required to operate in an ambient temperature to -25 Degrees F.