You can change the sensitivity of the mouse as well. *Not all that portable. My old pair were 9s and fit fine, but these were just too short. Edit: I was putting them in the wrong ears and for some reason that makes them not work correctly. 5 fits in the other styles. To wear around dry, theyre great. I like the zipper on the sides, it adds some style. Ordered another pair went a size up to 10x wide and perfect. Son estantes de metal suficientemente sólido. Now instead of scratching the inside where the hook goes, I get scratches on the outside where it touches the trunk.