Two, I think there are so many products out there and different kinds of surfaces to possibly use chalk paint with that it gives a crazy amount of combinations and ideas. (ourstoriedhome.com)
Using this feature, the mouse's sensor will detect what kind of surface you're playing on and adjust its feedback accordingly. (tomsguide.com)
If your cat seems to prefer eliminating on a certain kind of surface or in a certain location, you'll need to make that surface or its location less appealing. (aspca.org)