Rubber Ear Tips
While part of the AirPods Pro redesign, the rubberized and interchangeable ear tips are a significant enough feature to highlight separately. Those rubberized ear tips will allow for better noise isolation, but could also allow AirPods Pro to fit in a wider variety of ears than regular, non-interchangeable AirPods.
AirPods don’t fit every ear, which has been a consistent complaint about them since they debuted. Aside from resolving that, the rubber ear tips could also mean that AirPods Pro will be a bit harder to knock out of your ears. And, presumably, AirPods Pro will come with several ear tips, which users can swap out or replace at will.