[Introduction]：E50-900NW20SX wireless module is an ideal solution for IoT wireless connectivity below 1GHz for smart home, security, lighting, building automation and metering. The module is equipped with Silicon Labs' EFR32FG23 series chips, which can achieve wireless broadcasts up to 0.3~2.5 kilometers with minimal data loss in dense urban and canyon environments. At the same time, the module also carries firmware that supports WM-BUS bus technology. The wireless module firmware is developed based on the EN13757-4/3 European standard, which can realize seamless SUB-GHz RF communication protocols between smart general meters, data concentrators, mobile meter reading equipment and heat distribution meters.