AIRLINE APPROVED: The Sherpa On Wheels Pet Carrier is airline approved and part of our Guaranteed On Board program, which provides comfort and peace of mind to pets and their owners; it's perfect for traveling by air, bus, car, or train IN-CABIN FRIENDLY: Designed to fit under most airplane seats in compliance with FAA regulations; also features mesh wall panels for ventilation, escape-proof locking zippers, waterproof interior base, and a removable machine washable cozy liner EASY-GLIDE MOTION: The two front spinner wheels allow for smooth steering in any direction, with the two recessed wheels at the rear providing steady motion for safe and comfortable travel USE AS A ROLLER OR A TOTE: The detachable pull handle can be converted into an adjustable shoulder strap, transforming the rolling carrier into a pet tote or a duffel bag for your comfort and convenience MULTIFUNCTIONAL: The pet carrier can also function as a pet wagon or a portable soft-sided crate for regular outings and vet visits with cats and small dogs PRODUCT DETAILS: Black, One Size, 20" x 12.25" x 10.5"; fits pets up to 22 pounds; Flag not included CHOOSING THE RIGHT SIZE: Choose the perfect carrier size based on your pet's measurements, followed by their weight; make sure not to exceed the maximum weight limit, and allow enough space for your pet to change positions inside the carrier