This new dog backpack will give your dog maximum comfort and convenience when hiking with you. The backpack is designed with a removable pack, so you can easily take the weight off his or her back during rest stops. Large storage pockets hold food, water and other gear. Made with extra-strong nylon for durability. Bonus feature: The "quick release" leash holder for use when approaching other hikers, dogs, wildlife or park rangers. Simply grab leash handle and tug to release from holder. Available in 4 sizes: Small - Up to 18 lbs with a girth up to 25"Medium - From 18-50 lbs with a girth of 26"-32" Large - From 50-79 lbs with a girth of 30"-40" X-Large From 80 Lbs and over with a girth of 36"-48"