Thermocouples are best used for measuring temperatures that can go above 100 °C.
This is a wire with screw mount 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 metal sleeve braid so it can be used in high temperature measurements such as heaters and ovens.
Best used with a thermocouple amplifier such as the MAX6675 or MAX31855

• Type: Thermocouple Type K
• Temperature range: -50 to 300°C
• Accuracy: < 300°C ± 1.5°C
• Length: 100 cm
• Color: Metal.