ADAM-652S1 is an industrial-grade Ethernet switch and single-mode fiber converter. It is designed to help extend an Ethernet network up to 15 km through areas with electrical noise interference. ADAM-6521 has one fiber optic and four RJ-45 ports. With single-mode fiber transmission, you can prevent noise interference and achieve transmission distances up to 15 km. Thus, ADAM-6521S is especially suitable for industrial environments with long-distance Ethernet networking needs, e.g. warehouses, transportation, environmental monitoring, and many more.