Here is the blurb on the 1K version of this part from the Precision Resistor Website. The compensation factor is the same in this 2K part but the value is 2K so that 100K input resistors can be used in the voltage summer section of a linear to log convertor. The tempco is about 3 inches long with leads. The actual tempco element is about 0.12" thick and 0.4" long. I suggest the use of thermal grease or epoxy to attach it to the transistor pair to insure good thermal contact. The advantage of thermal grease is that you could remove and reuse the part if desired, with epoxy... not so much.

PRC Fact

The TCR Tolerance on the 1K Compensators is +3500 ppm/°C. Meaning, if you are looking for a systems offset of +3350 ppm/°C. to +3450 ppm/°C, we are confident you can achieve dramatic results with our standard off-the-shelf compensators. The actual TCR of a standard 3500 element is very close to +3350 ppm/°C. at 25°C. and lower than +3450 ppm/°C. at 100°C.