A HART Scientific 9100 HDRC (Handheld Dry‑well Temperature Calibrator) is a portable, precision instrument used to calibrate thermocouples and RTDs on-site or in the lab. Key specs from the manual:
• Temperature range: 33 °C to 300 °C (92 °F to 572 °F)
• Accuracy: ±0.5 °C between 33–100 °C; ±1 °C between 100–300 °C; ±2 °C with larger probe holes 
• Resolution: 0.1 °C display
• Heats up from 35 to 300 °C in about 9.5 minutes, stabilizes in roughly 3 minutes