Quadlock insert for magnetic car phone stand or car vent magnetic phone holder, a steel washer needs to be glued in.
Steel washer I used (what I had in house): 25 mm OD, 10 mm ID, 2.5 mm thick
To lock/unlock in the phone case you can use a 1 euro coin or similar, put in the central cave and twist.
Text me/comment if you want different washer caves with dimensions.
The author marked this model as their own original creation.