Summary

I've created a thing to mount a mobile phone on a tripod.

You will need a small hair tie or household rubber band to join the pieces together.

Assembly:
I first pulled the hair tie through the hole of the upper part. Then I slowly pushed the upper part into the lower part and pulled the elastic band on with a toothpick and pushed it over the holding point. A little dexterity and one or two attempts may be necessary ;-)