Extech 42540-NIST- NIST Calibration Certificate High Temperature IR Laser Thermometer features: Rugged thermometer with 12:1 distance to target ratio; Widest temperature range from -58° to 1400°F (-50 to 760°C); Built-in laser pointer identifies target area; High 12 to 1 distance to target ratio measures smaller surface areas at greater distances, etc.