1. The concentration unit ppm and mg/m3 can be switched and displayed by one button. 2. USB high-speed data transmission, can be downloaded, printed and stored. 3. There are 100 groups of alarm records as standard, and more than 100,000 groups of stored data are optional. 4. The Chinese and English operation interface can be switched arbitrarily. 5. The standard alligator clip can be used for protection while working., Manufacturer: LLOOPK