Sensor: Built-in NTC thermistor Data Interface: USB Interface Data output: USB socket directly connected to the computer Instructions for use: long press the key for more than 4 seconds, after the interface shows ▶ sign, it means the instrument start recording. Application: It is mainly used to monitor and record the temperature data of foods, drugs, chemicals, etc. during storage and transportation. It is widely used in all aspects of warehousing, logistics and cold chain, such as refrigerated containers, refrigerated trucks, refrigerated bags, cold storage, Laboratory etc. Type: Digital Temperature Data Logger Power supply: Built-in wide temperature CR2032 button battery or USB interface Material:ABS colour:White + Blue Package Contents: 3 x Digital Hygrometer 3 x English manual Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.