Insight is the world's largest manufacturer of aviation temperature probes. The temperature probe measures the engine's pulse and therefore is crucial to optimum performance. Insight's probes are built and tested to the highest quality control standards to ensure long life and high performance. The Gasket Probe uses the same J-Type thermocouple as the Spring Probe. This probe replaces the gasket on 18mm spark plugs. The J-Type thermocouple has red and white color coded wires. Note that the spark plug plugs in some engines may run 50 to 100 Fahrenheit degrees hotter than the thermowell. The copper gasket can be annealed just like a standard spark plug gasket.

The gasket probe is recommended for use anytime the spring probe cannot be used. Aircraft fitted with thermowell TANIS preheaters should use the CHT Gasket probes.