The primary difference between Type J and Type K thermocouples is the measuring range, and the sensitivity. Type K is the most common general purpose thermocouple with a sensitivity of approximately 41 µV/°C. A wide variety of probes are available in its −200°C ~ +1350°C / -330°F ~ +2460°F range. Type K wire color standard is yellow (+) and red (-). Type J has a more restricted range than type K (−40 ~ +750°C), but higher sensitivity of about 50 µV/°C. Type J wire color standard is white (+) and red (-).