01 High-definition color screen display: the real-time values of the four items are displayed at the same time/Chinese and English can be switched, and the gas concentration is displayed in real time. 02 Triple display limit alarm: alarm threshold/acousto-optic vibration triple alarm prompt, when the detected gas concentration is high. 03 Direct-charge lithium battery is energy-saving and environmentally friendly; USB direct-charge lithium battery has a built-in 1 800mAh lithium battery, and the USB interface is directly charged. 04 Waterproof, dustproof and explosion-proof; good materials, high-quality casting, tough and wear-resistant, good in hand. 05Data storage function: record data, playback function, can continuously record 120,000 data