This is a handy phone holder for the IKEA Skadis system. It's designed to keep your phone steady and upright while you work around your shop. The phone holder fits the OnePlus 7T Pro perfectly with an Otterbox cover, which is 8 cm wide. However, it also works for wider phones and tablets up to 13 cm.
Note that this holder is not intended to hang on a moving part, such as a sliding or swinging door. Larger tablets can also fit, but this is at your own risk and you may need to use 4 or 6 hooks to distribute the weight across the holders.