Abstract: A thermal head for device under test having a gimbal fixture and a protective casing and an air chamber having an air inlet hole and a plurality of O-ring grooves to form a pneumatic control mechanism, comprising (a) a cooling chamber within the protective casing having at least one inlet and at least one outlet formed on each of the opposite edge of the chamber for the flow of a cooling fluid from the inlet to the outlet to provide a cooling temperature to a device under test which comes into contact with the thermal head; (b) a metal plate being formed below the cooling chamber, wherein the metal plate touches the surface of the device under test when the thermal head is in operation; (c) an air gap formed between the cooling chamber and the metal plate, wherein the size of the gap depends on distance between the cooling chamber and the metal plate, wherein the cooling chamber moves relative to the metal plate; and (d) a pair of coil spring mechanism disposed in between the base of the metal plate and a jac