Compact 4G LTE IoT gateway with RS485 serial interface for Modbus RTU and industrial sensor networks. Converts RS485 serial data to cloud-accessible Modbus TCP over 4G LTE. Ideal for energy meters, solar inverters, HVAC controllers, fuel level probes, and water meters. DIN rail mountable, wide voltage input (9–50 V DC), IPsec/OpenVPN VPN tunnels.