Thermocouple Type K 1/8 Diameter Closed Tip EGT Probe to be used with Digital Stepper Motors. 

EGT's are one of those numbers that you can't overlook once you start modifying a diesel truck, but at the same time, it's a number that few factory trucks allow you to see. Using this probe and an aftermarket gauge means you could stay on top of your truck and what's going on under the hood!