1.Expandable for More Space:This cat carrier with an expandable back design provides additional space and enhanced air circulation.With a simple expansion feature, it transforms into a spacious home, doubling the interior space of the expandable cat carrier. Your pet will have ample room to move around, relax, and enjoy the journey to the fullest.approved under seat. 2.Breathable & Visible Cat Carrier: This kitten backpack carrier is made of mesh fabric on three sides to ensure ventilation and visual-ability, suitable for pets to travel for a long time and convenient for you to see your pet inside. The top of bag can be opened, and your pet can extend its heads to satisfy curiosity. 3.Airline Approved Cat Backpack: The dimension of cat carrier bag: 12.6" L x 11.4" W x 16.5" H, suitable for cats, small dogs or small animals that up to 15lbs weight. Large backpack for cats to carry, taking pets to travel, hiking, walking or cycling, it also suitable for most airline approved under seat. 4.Foldable & Easy using:Made of high-quality, scratch-resistant and durable materials, the pet backpack will remain in good condition even after long-term use. The foldable design of the backpack makes it easy to store without taking up extra space, so you can easily store it when not in use