Thermocouples are best used for measuring temperatures that can go above 100 °C. Thermocouple Type-K Glass Braid Insulated is a bare wires bead-probe which can measure air or surface temperatures. Most inexpensive thermocouples have a vinyl covering which can melt at around 200 °C, this one uses a fiberglass braid so it can be used in high temperature measurements such as heaters and ovens.
Note: There are some thermocouples that the red and yellow wires color-coded wrong. It will not damage the thermocouple or sensor if the wires are connected wrong, but temperature readings will go the 'wrong way', so if you find that the temperature is dropping when you heat up the sensor, try flipping the wires.
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