1m K Thermocouple

This 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. There's a small piece of heat shrink on the end to keep the fiberglass from fraying. If you're using at >250°C temperatures, simply remove it with a small blade.

K type thermocouple with glass over-braiding
Good up to 500 °C (900 °F)!
Color-coded wires
1 meter long (a little more than 3 feet)
Best used with a thermocouple amplifier such as the MAX6675 or MAX31855