2.5" diameter, car coasters, washable. 
The coaster is with a small curved gap, easy to install and remove; It features anti-slip performance and good elasticity, the coaster can firmly grasp the flat surface at the bottom and prevent slipping; With waterproof and quick-drying neoprene, easy to clean after being soiled by splashing drink. 
These go in the cup holder of your car but you can also use them in your home.
Keep your car cup holder clean and fun. You can change them for different themes, holidays etc..