Case uses aluminum; the covered and the box use double-ring rubber seal ring thread lock structure. Therefore, the instrument has good anti-corrosive and water-proof performances. Radial-type meter is bend tube type. It is small and beautiful. WSSX series electric contact bimetal thermometer equip with electric contact device that is Mechanical electrical contacts. When the temperature of measured media is changing, thin shaft on the free terminal and steering linkage will drive pointers and contact to indicate temperature changing value on the scale plate. When it is contact or disconnect with fixed contact, it will drive the relay or contactor to control temperature or alarm in circuit system Accuracy grade: 1.5 Error deviation limit: basic error*1.5 Contact rated power:*0VA the maximum working voltage of Contact:**0V or **0V the maximum working current of contact:1A