All air vent mounts inevitably block part of the air flow, but the phone clip of this car phone holder extends farther from the air vent, and the area to block the air flow is small. Overall, it has little effect on the airflow at the outlet.
It depends on how your car air vent are constructed. The key is to make it easy for you to see and operate your phone. In general, you can operate your phone more easily and see your phone more clearly when the car phone holder is mounted closer to the dashboard.
This vent phone mount for car fits car vent that has horizontal or vertical strip blades, but not for round air vent. It adopts a hook connection design, which is equally stable and can fit a narrower air outlet compared to the previous model.