The combustible gas monitoring device developed by our company is suitable for continuous monitoring and early warning of gas concentration in underground confined Spaces such as gas valve Wells, water supply and drainage Wells, power Wells and communication Wells. The product is an integrated iot device consisting of a laser gas sensor, a temperature sensor, a manhole cover status switch, a water level switch, a pressure sensor, an ultra-low power wireless communication module (4G/NB-IOT), a clock and a high-performance microprocessor. It is an intelligent terminal device that adopts ultra-low power consumption design, advanced laser sensing technology and Internet of Things technology to monitor the concentration of combustible gas in the installation environment online. No open cover magnetic bar boot/wake up function, easy to deploy on site. With waterproof and explosion-proof, less interference by environmental factors, high sensitivity, high precision, wide range, corrosion resistance, good stability, no poisoning, not dependent on oxygen, long life, maintenance-free and other significant characteristics, it has well solved the problem of underground confined space combustible gas concentration monitoring and data access, providing an important guarantee for urban gas safety monitoring.