Good quality, but could be better
My cat usually digs a lot while is in the litter box, since the back part is higher, is very usefull for us. But in the front, the concave part, accumulates sand in the edge (that is removable), when the cat digs from upwards. You can see this when you uninsert this removable part to clean the box, probably because of this part is concave. The other parts of the edge doesn't accumulates sand/rocks.