Available in 20 pieces. A FEMA stainless steel thermocouple temperature gauge uses a thermocouple made of two different metals, typically stainless steel and another metal such as nickel or chromium. When it comes into contact with a heat source, an electrical potential difference is generated between the two metals that varies with the temperature. This potential difference is then measured by the temperature gauge and converted into a temperature reading. Essentially, the temperature gauge has a display that shows the temperature detected by the thermocouple and can be configured to emit warning or control signals based on the detected values. In this way, the stainless steel thermocouple temperature gauge allows you to precisely monitor the temperature of a specific environment or process.