The 303139, 303140 are ultra high precision molded surface mountable resistors offering all the elements of precision; including low TCR, tight tolerance, long term stability, low noise, low thermal EMF, and non-measurable voltage coefficient. One of the important parameters influencing stability is the temperature coefficient of resistance (TCR). Although the TCR of foil resistors is considered extremely low, this characteristic has been further refined over the years. These resistors utilize ultra high precision Bulk Metal®Z-Foil.