This is a Digital Thermocouple K-Type Thermometer.
It measures variance in temperature from between the two K-Type Thermocouples.
Benefits:
Differential Temperature Measurement
Select between Celsius and Fahrenheit
Overload display alert when input exceeds measurement range
Hold mode – holds current reading and ceases taking other measurements
Easily portable – take it anywhere you need it
Robust casing
Large, clear LCD
General Specifications:
Display: 3 ½ digit liquid crystal display with maximum reading of 1999
Powered by: 1 9V battery
Power Current: approx DC 3mA (typical)
Dimensions of Thermometer: 5.5 (w) x 11.5 (l) x 3 (d)cm (2.5 x 4.7 x 1")
Dimensions of Screen: 4 (w) x 2 (l)cm (1.6 x 0.8")
Length of Thermocouples: 75cm (29.5")
Weight (Including Battery): 190g
Electrical Specifications:
Temperature Scale: Celsius or Fahrenheit
Measurement range: -50°C to 1300°C (-58°F to 1999°F)
Resolution: 1°C or 1°F
Accuracy:
0.1°C ± (0.3%rdg +1°C) -50°C to 199.9°C
0.1°F ± (0.3%rdg +1°F) -58°F to 199.9°F
1°C ± (0.3%rdg +2°C) -50°C to 1200°C
1°C ± (0.6%rdg +2°C) 1200°C to 1300°C
1°F ± (0.3%rdg +2°C) -58°C to 1200°C
1°F ± (0.6%rdg +2°C) 1200°F to 1999°F
Temperature Coefficient: 0.1 x the applicable accuracy spec per °C from 0°C to 18°C and 28°C to 50°C (32°F to 64°F and 82°F to 122°F)
Input Protection: 60V DC or 24V AC max input voltage on any combination of input pins
Reading Rate: 2.5 times per second
Input Connector: Accepts standard miniature thermocouple connectors
This particular one was bought on eBay for 50 Dollars(US).