One of the most common metric circular connectors is the M12 A-Code. The corresponding IEC 61076-2-101 standard covers pin counts 2 - 17. However, generally, the most common pins counts are the 4 and 5 pin variations. This connection is typically used for sensor actuator applications or for power supply connections. Within the HARTING portfolio there are PCB mount jacks, crimp and field installable plugs, overmolded assemblies and PushPull locking variations. Voltage ratings vary for these M12s based on the pin count.