1. High-precision laser sensor, accurate and sensitive, so that the original shape of the contaminated particles is exposed. 2. Real-time monitoring of humidity, temperature, PM2.5. 3. When PM2.5 exceeds the alarm value, the instrument flashes red data. 4. Short press SET to set the alarm value, and the screen flashes to display the current alarm value (the instrument default alarm value is 115??g/m3). 5. With it, you can easily grasp the performance of the purifier. 6. Built-in 580mAh lithium battery, with the charge, not afraid of power off. Fast charging in 30 minutes, full charge for 4.5 hours or more. 7. Compact and portable. 8. Suitable for multi-scene use, such as car, office, outings, home, etc. Specification: 1. PM2.5 measurement range: 0-500 micrograms per cubic meter. 2. PM2.5 single response time: less than 1s. 3. PM2.5 comprehensive response time: less than or equal to 10s. 4. PM2.5 resolution: 1 microgram per cubic meter. 5. Temperature measurement range: -10 to 50 degrees Celsius. 6. Temperature measurement accuracy: +/- 0.3 degrees Celsius. 7. Humidity measurement range: from zero to ninety-nine percent RH. 8. Humidity measurement accuracy: +/- 3 percent RH. 9. PM2.5 sensor: Climbing laser particle sensor. 10. Charging mode: DC 5V 500mA Micro USB interface. 11. Built-in lithium battery: 580mAh. 12. Net weight: 86g.Specification: Package Weight One Package Weight 3.87kgs / 8.54lb One Package Size 25cm * 21cm * 21cm / 9.84inch * 8.27inch * 8.27inch Qty per Carton 4 Carton Weight 16.40kgs / 36.16lb Carton Size 44cm * 44cm * 27cm / 17.32inch * 17.32inch * 10.63inch Loading Container 20GP: 510 cartons * 4 pcs = 2040 pcs40HQ: 1184 cartons * 4 pcs = 4736 pcs