Cade Outdoor Hiking Camping Training Adjustable Dog Saddle-harness Bag Large Capacity Dog Backpack with Reflective Stripe [The Lucky Ones Will Get Free Gift: Pet Bath Massage Brush] Please choose the appropriate size according to the size of your dog. It contains space for food, water and other gears.The belt can be adjusted to the size for the chest and it is adjustable in the neck (circumference) part. Neck circumference is adjustable;The bag inner have sandwich air net, very comfortable ; With light reflection stripe on the backpack,you can see your dog's activities on night Medium Size,Chest Girth 27&quot;- 31&quot;,Bag Length 8.7&quot; * 12.5&quot;,Pocket Length 4&quot; * 5&quot; Stylish, Lightweight and Washable,Made of R/S PU/420D PU;The PU mesh in the middle is breathable and cooling, bring your loved dog comfortable feelings Convenient pockets for carrying food, water, and gear for you and your pet wherever you go