Collars with Martingale system are designed for dog breeds such as the greyhound, whose head diameter, at its widest part (where the ears are), is equal to neck’s diameter.
What Martingale system does is to adjust to the animal neck in case it pulls with too much impetus, or simply try to take it off.
These collars, despite being specific for certain breeds, are highly recommended for the rest, because they are wider than the classic buckle collar, they do not damage the dog’s neck when they pull, besides being very comfortable and easy to put on and take off. A part, its amplitude makes them stand out more in the dog because they are more visible and if you have a leash to match the collar, you will show off the coolest dog!
To know the size you should choose for your friend, see our SIZE GUIDE.