VARIOFACE Interface Modules with LED Indicators Phoenix Contact VARIOFACE Interface Modules with LED Indicators enable a fast, fault-free transition between a D-sub or flat ribbon plug assembly to a discrete wire using a screw-clamp termination. The LED indicators illuminate when the signal is present, allowing quick visual inspection for monitoring and troubleshooting. Phoenix Contact VARIOFACE Professional Interface Modules with LED Indicators feature a patented design to reduce space requirements within the control cabinet and provide the ability to use the ZB marking products for easy, quick, and consistent labeling.