Low temperature platinum thermal resistance bulb is used for the measurement and monitoring of lubricating oil, cooling water, bearing temperature and air temperature of various Marine engines. Since the delay characteristic (response speed) is an important factor for low temperature use, the thermal resistance bulb is designed so that its resistance element has excellent thermal conductivity to minimize the heat that may be generated in it. The double protection tube does not affect the characteristics and maintains the same characteristics as the single protection tube type.