The Hart Scientific 1590 Super-Thermometer is a best-selling thermometer because of its ease of use, 1 ppm high accuracy, built-in software, and reasonable price. Temperature is read directly on the color display in your choice of scales. There are no manual resistance-to-temperature conversions. Resistance is converted to temperature for you using the ITS-90 algorithm in any one of the instrument’s ranges. Up to 16 independent sets of probe characterizations can be stored in the 1590’s memory. Switch SPRTs and simply call up its reference identification number.