Holder for trailer hook electric adaptor (Seat Ibiza 6J)

I needed a good place to store my 13 to 7 pin adaptor for the trailer hook's electrical connector on the car. It is a Seat Ibiza 2010. I came up with this little holder that attaches with the left rear lights fastening screw. - Remove the original fastening screw (keep it somewhere...) - Put on the printed distance washer on the lamp's screw - Put on the printed holder - Put on an ordinary washer and a M6 nut to keep it all in place. (Make sure you can remove the nut "road side" in case you need to change a bulb.)