Made of nylon fabric, lightweight, durable and waterproof, pet hair free and blackout. If your dog is anxious or gets car sickness, the calming blindfold makes your dog calm. Calming dog eye mask can make it easier for you to groom your dog, such as bathing, trimming dog claws, cleaning ears, and cutting hair. Dogs resistance to emotions can be relieved and its easier to cooperate when minor surgery or physical examination without anesthesia is performed. Size S : mouth circumference 12-18cm, neck circumference 18-32cm Size M : mouth circumference 14-22cm, neck circumference 20-44cm Size L : mouth circumference 18-26cm, neck circumference 26-58cm Size XL : mouth circumference 24-32cm, neck circumference 32-64cm.