Connect serial equipment, local IP devices, and wireless clients through a compact cellular gateway built for industrial sites. RUT206020000 combines a 4G LTE Category 4 radio, two SIM slots, two Ethernet ports, and 2.4 GHz Wi-Fi in an 83 x 25 x 83 mm enclosure. Its six-pin terminal block provides RS232 and RS485 connectivity for controllers, meters, sensors, and other field equipment that still depends on serial communications. RutOS supplies routing, NAT, firewall policy, DHCP, DNS, IPv4/IPv6 operation, port forwarding, static routes, VLAN controls, traffic controls, logging, diagnostics, configuration backup, and firmware management. HTTPS WebUI and SSH provide local administration, while Teltonika RMS supports centrally managed devices after enrollment. Dual SIM capability and failover functions support cellular backhaul planning where service continuity matters, subject to the installed SIMs, carrier service, antennas, and network coverage. Power the router from a 9-57 VDC two-pin socket, active IEEE 802.3af PoE Class 0 on the LAN Ethernet path, or passive PoE input on LAN1 using spare pairs at 16-57 VDC. This combination distinguishes the RUT206 for compact cabinet, vehicle, kiosk, utility, and machine installations that need both legacy serial access and modern cellular routing. Match the selected cellular service and antenna system to the deployment region before installation.