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Opto 22

Opto 22 was founded in 1974 in Southern California by engineer Bob Engman, starting with 22 optically isolated solid-state relays. In 1978 the company developed the first plug-in I/O modules and created the color code still used to identify them: yellow for AC input, black for AC output, white for DC input and red for DC output. Opto 22 remains privately held and engineer-run, designing and building its products at its factory in Temecula, California. This collection carries Opto 22 standard-series and G4 Series digital I/O modules, including DC and AC input and output modules, as used and surplus inventory for industrial automation and control repair. Fast shipping from American Industrial Parts Group.