【Collapsible and Expandable】- The cat backpack carrier with an expandable back that gives your pet more room to move around and reduces their anxiety. Collapsible design helps you to save space when not in use..【Breathable and Comfortable】- 5-side mesh windows for optimal airflow, 3 entrances (top, front, and back) allow your pet to enjoy the outside scenery and easily entry into the carrier. 2 washable and removable pads for your pet to rest comfortably..【Travel Friendly】- Designed with a breathable sponge back, widened adjustable shoulder straps, and a chest buckle, these features help relieve the pressure to your back and shoulders, making the pet backpack a breeze to wear for long trips..【Larger Size than Any Others】- Expanded size: 21.7" x 13 x 15 inch, unexpanded size: 13'' x 9.8'' x 15'. Fits the pets under 15 lbs, like most cats, small dogs, rabbits..【Durable and Functional】- Made from quality 300D polyester and scratch-resistant mesh, this pet backpack carrier is sturdy and safe for your pets. And it's lightweight and portable, ideal for traveling, camping, hiking, visiting a veterinarian, or walking in the park.