⭕ This is a Fluke Hart Scientific 1590 Superthermometer II with the 2590 Multiplexer. 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 instruments ranges. Up to 16 independent sets of probe characterizations can be stored in the 1590s memory. Switch SPRTs and simply call up its reference identification number. For the Hart 1590, the Hart Scientific 2590 Mighty-Mux II has a cascading ability that lets you have up to 50 channels by chaining more than one Mux together, and you can now set continuous constant current levels on each channel to avoid self-heating effects. Whatever your application, a Mighty-Mux will make it easier and more efficient. The Hart 2590 has low thermal EMF relays that are hermetically sealed and magnetically shielded. Youre making true four-wire measurements with a floating guard and support for up to 20 mA of drive current. Can be delivery.