Please measure your pet before purchasing: This airline approved expandable pet carrier can be extended on 3 sides. The size of the pet carrier is 17.5"L x 12"W x 11.5"H and the expandable size is 30"L x 27"W x 11.5"H by expanding the 3 mesh windows. This carrier weighs about 2.5 lbs and fits pets up to 12 lbs. Suitable for small or medium dogs and cats. Breathability and Comfort: The 5-sided mesh design of this pet travel bag provides plenty of breathability and visibility in any situation, allowing your pet to observe the outside world. With 3 expandable compartments, this cat carrier provides extra room on 3 sides for your pet to stand and turn around without bending or contorting on 3 layers of comfortable removable padding. Convenient and Safe: This dog travel bag securely attaches to the front seat of your car with a seat belt and shoulder strap, keeping your pet restrained and safe while driving. Designed to meet TSA and IATA requirements for under-seat use. Carefully sized to meet the under-seat requirements of domestic and international airlines. Strong and Durable: This airline-approved dog carrier is made of high-quality polyester and mesh, which will not cause the top to collapse. The self-locking zipper design of the pet carriers provides your pet with a spacious space, ensuring their safety. Wide Use & Easy to Carry: Portable; Carried with an adjustable shoulder strap; Dog/Cat Carrier; Car seat cover; Luggage cover; Under airplane seats, ideal for long trips, car rides, plane rides, vet visits, vacations, potential airport delays, layovers, and family use.