Micro B Round Panel Mount Extension Cable - 30cm . If you need to add a panel-mount connection for USB Micro B, but don't have the time or ability to cut a custom oval or square hole, this Round Panel Mount Extension Cable is the easiest and fastest way to panel-ify your existing HDMI kit. The adapter is about 30mm in diameter, so you can drill a hole in your wood, plastic or metal with a common hole-saw or bit, no special shapes or filing required. Un-screw the plastic nut, insert the plug and re-attach. Ta-da! Now you have a USB Micro B jack on one end and a Micro B plug on the other! It's designed to easily attach to a panel up to 16mm thick (or 0.625in), or as thin as a few mm. Perfect for adding a Micro B port to your project enclosure! We like this plug in particular for its solid body and 'forgiving' plastic lip that hides the drill hole.