The MH-441D methane gas sensor is a general-purpose intelligent infrared gas sensor that uses the non-dispersive infrared (NDIR) principle to detect methane gas in the air. It exhibits excellent selectivity and is not oxygen-dependent. This sensor is a compact, high-performance device that combines mature infrared absorption gas detection technology with micro-machining and sophisticated circuit design. It is easy to use and can directly replace catalytic combustion elements, making it widely applicable in various situations where methane and explosive gases are present.