This refers to a Sensata temperature sensor. The part consists of 249-4-B-80-60-2-63-1, with each number having a specific significance.
The first three digits, 249, refer to the manufacturer (in this case, Sensata). The next two digits, 4 and B, indicate the product series. The next two digits, 80 and 60, refer to the nominal voltage in volts. The next digit, 2, indicates the nominal wattage in watts. The 63 refers to the location of the sensor in terms of climate. Finally, the last digit, 1, indicates that it is a single-stage temperature sensor.