An alternative to the Thunder Shirt, this Calming Collar is infused the the Essential Oil, Lavender. For all types of anxiety, fear, and over excitement issues. The fragrance of lavender is calming, relaxing and balancing – physically and emotionally! These collars can also be used to cool dogs off in the summer. They can be soaked in water, and put into the refrigerator for cooling. Sizes are adjustable: medium, large and extra-large.