1. Comfort & Safety: Breathable mesh fabric of large areawell ensure the comfort for your pet--4 big breathable windows of pet travel carrier backpack are designed for visibility and air ventilation. Dogs or cats can observe the surroundings well, feel relaxed and have a good mood in the carrier. Note: Because the bag is soft, it cannot maintain its perfect shape. And the maximum weight is 5 pounds. 2. : The pet carrier backpack is made of sturdy, durable, lightweight polyester material, which is not easy to break and tear apart when your dog is playing. Safe and non-toxic, no need to worry about damage done by clawing or gnawing, ensure pet's comfort. 3. Ergonomic Design: This dog/cat backpack is ergonomically designed to reduce pressure on your shoulders and effectively increase the comfort level of human body. The entry of the backpack is very large and can be flipped at 180 degrees. It is very convenient for the pets to enter.