the model is a remix designed for convenient smartphone mounting on a moving arm.
other compatible parts can be found here:
https://www.printables.com/model/647794-flexible-sturdy-phone-arm-100-printed
the base for the modification was the work of the author @3Dmaker
The author remixed this model.
added the ability to mount the phone on a flexible arm:
https://www.printables.com/model/647794-flexible-sturdy-phone-arm-100-printed