Kramer C-UAM/DC35-3 Fiber Optic Power Cable

The Kramer C-UAM/DC35-3 is a 3-foot power cable that takes 5V from a USB Type-A port and delivers it on a DC barrel plug, powering a small device from a spare USB socket instead of a separate mains adapter.

In practice it is the cable that powers an optical HDMI cable's transmitter or a similar low-draw accessory from the display's own service USB port, which removes one power brick and one outlet from the install.