4G router can only work in the 4G network?

No, 2.5G, 3G, 4G router key difference lies inside the network communication module, 4G router, there are two, one is a quasi-4G essence WCDMA HSPA + technology, not true 4G. Another is the real 4G LTE technology. For example, The E-lins technology, H685 and H820 series router, specifically for substance networking router wireless communication design, use of public LTE / WCDMA / EVDO / HSPA + wireless long-distance network to provide users with data transfer function. The product uses a high-performance industrial grade 32 communications processors and industrial grade wireless module for embedded real-time operating system software support platform, while providing an RS232 (RS485/RS422 optional), one or four Ethernet network and a WIFI interface, which can connect serial devices, Ethernet devices and WIFI equipment, transparent data transmission and routing functions. The products have been widely used in the networking industry chain in the M2M industry, such as video surveillance, three tables (meter, water meter, gas meter), smart grid, intelligent transportation, smart home, finance, mobile POS terminals, supply chain automation, industrial automation, intelligent building, fire, public safety, environmental protection, meteorology, digitized medical, telemetry, military, space exploration, agriculture, forestry, water, coal, petrochemical and other fields.