This is an extension of Sony Xperia Z car mount (http://www.thingiverse.com/thing:84674) with a built charger and NFC tag holder. I used the NFC tag to enable/disable functionality as I have multiple chargers and want a different functionality in different places. I normally enable bluetooth for the car hands free and start GPS navigation. I used a mini USB port as it seems to be more available then micro ports and I have plenty of mini cables lying around. Electronic parts are sourced from RS online: RS Stock No. 666-1099 701-9950 Assembly: Pull out middle spring connector and also cut middle pin in the bottom. Shorten the other 2 bottom pins. Pull the wires through the holes in the holder first, then solder the 2 side pins on min usb connector to wires. Push the min usb connector into place (note: The picture of the connectors with the wire is only for illustration of how the connections are to be made. The soldering has to be done in place once the wires are threaded through the body of the dock). Push the spring loaded connector in place as well. Cut the remaining wires to length and solder to the spring loaded connecter side pins. Make sure that the ground pin goes towards the middle of the phone. Cover the bottom holes and back holes with the cover plates. I used acetone to secure them in place. Place NFC tag in top left corner. Program your NFC tag. Enjoy :-)