These connectors run the automated world, from robot arms and photoelectric sensors to PLCs, IO-Link devices, and Ethernet switches. The original metric circular connector, they continue to be the standard today. They screw together tightly to protect against contaminants and hold firm against high vibration. Each one has a coding that indicates a unique keyway, preventing mismated connection errors before they happen. The coding also tells you whether a connector can send power, control, or data. Some can send a combination of the three, reducing the need for multiple connectors.