It provides power to HD-31C HDMI Compact Switcher and MHDCP-EQH HDMI EQ AV Extender if it is not getting enough power from the HDMI port. NOTE: Must be used with HD-31C REV1, REV2 & REV3 or MHDCP-EQH. (Input Voltage: 100-240v 50-60Hz / Output...[more info]