When sourcing EGT sensors, you must prioritize the sensing element type, typically K-type thermocouples for high-temperature accuracy. Ensure the temperature range covers at least 0°C to 1200°C for automotive or industrial exhaust systems. Pay close attention to the probe material, where Inconel 600 or Stainless Steel 310 is preferred for superior oxidation resistance. Additionally, verify the response time (ideally <250ms) and thread size compatibility (e.g., 1/8" NPT) to ensure seamless integration with the manifold.