Only 2 connectors and 2 of the different mounting plates. All 3 have rail maiunting plates installed. Let me know if you need the connectors and or plate. The Advantech ADAM-4520 is an RS-232 to RS-422/RS-485 isolated converter designed for industrial automation and motion control applications. It is manufactured in Taiwan by Advantech and provides reliable and secure communication between devices using different serial communication standards.
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