The 1524-P4-256 is a two-channel reference thermometer bundled with a 5615 PRT probe, designed to measure, graph, and record three sensor types (PRTs, thermocouples, and thermistors) with high accuracy. It features dual-channel simultaneous measurement capability, 15,000 time and date-stamped data logging measurements, and a real-time clock for comprehensive temperature monitoring. The thermometer delivers exceptional accuracy with PRTs up to ±0.011 °C, thermocouples up to ±0.24 °C, and precision thermistors at ±0.002 °C, utilizing current reversal technique to eliminate thermal EMFs. The included 5615 PRT probe operates from -200 °C to 420 °C (-328 °C to 788 °C) with 100 ohm resistance and 6.35 mm × 305 mm dimensions. This handheld tool is ideal for field applications, laboratory measurements, and data logging in calibration, compliance, and process verification scenarios, with specifications guaranteed from -10 °C to 60 °C ambient temperature.