1" ball mount that can be used as a standard RAM (size B) ball. RAM, Quad Lock, and a wide range of other companies make phone mounts for this. I strongly recommend the following mount and arm, but any phone mount compatible with a 1" ball should work.
https://rammount.com/products/ram-hol-pd4-238au
https://rammount.com/collections/popular-components-b-size/products/ram-b-201u-a
You can find alternatives or possibly better pricing at Amazon or Ebay.
This is printed in high quality PETG with stainless steel hardware. It clamps into a standard sized rocker switch knockout for a very solid feel. Our customers primarily use this in SXS vehicles going over very rough terrain with no issue.
Note: This requires access to the back of your rocker panel during installation. Purchase only includes the mount and stainless steel hardware, not the arm or actual phone mount. I have had no issue with this supporting phones or other small devices, but use at your own risk. We are not responsible for damaged devices.