Fiboo's Littter Mat is perfect to stop the litter from being scattered by the cat outside of the litter box while exiting it or by digging while in the litter box.
It's proven to reduce up to 90% of the gravel.
It is very easy to clean and durable.
It can be placed in different ways and in as many pieces as you wish, depending on factors such as the numner of cats in the household, the size of the litter box, the habits of the cat(s) and more. 
 
Note for placement: the lines must be parallel to the litter box door, with the direction facing towards the door.