The slow feeders have raised ridges or bumps that the dog has to navigate around. The aim is to make the dog eat more slowly and take smaller bites, which can help to promote healthy digestion and reduce the risk of health problems.
When selecting a dog slow feeder, it is important to choose one that is the appropriate size for your dog's needs. The feeder should be large enough to hold the appropriate amount of food, but not so large that it takes up too much space in your home. 
It is important to note that a dog slow feeder is not a substitute for regular exercise or a balanced diet. You should still provide your dog with regular exercise and a well-balanced diet to maintain their overall health and well-being. However, a slow feeder can be a useful tool for helping your dog eat more slowly and avoid the negative consequences of fast eating.