Modbus RS-485 Adapter, Product Type Modbus RS-485 Adapter, Series Commercial Series, Sub-Brand Macurco, Features 8-Bit Dip Switch Address Selector, Communication Is On A Modbus Serial Line, Mounts Behind the Detector Inside of a Standard 4 in x 4 in Electrical Box, The MRS-485 Monitors Sensor Type, Gas Level, and Trouble Status Communications, Tricolored LEDs Indicating Power, Test, and Communication Status, Overall Depth 1.75 in, For Use With Macurco 6-Series Gas Detectors