EASY TO USESimply point the thermometer at the object you want to measure and click to get a reading. the distance to spot ratio is 12: 1 can measure targets at a longer distance, the larger the object, the farther the measurement distance; the smaller the object, the closer the measurement distance.For high temperature, toxic or difficult to reach objects, to use of this product can be safely measured and range from -58~1472(-50~800)