Product Features: ? "Pop-Top": Pop up the expanding top of the carrier to give your pet room extra room to hang out! When using on the airplane itself, simply pop the top back down to allow the carrier to easily slide under the seat in front and comply with airline regulations! The mesh lining also gives them a chance to see your face, keeping them calm and happy ? STURDY & DURABLE DESIGN- Wire frame in both sides support the carrier to be more sturdy and prevent the sides from caving in like other soft-sided carriers. 2 zippered doors and zippered top allow your pets easy access. Back-pocket can store small goods. Strap on the carrier allows you to easily hook the carrier on top of your luggage for travel. ? GOOD AIR CIRCULATION- Mesh front, back, and sides allows air to circulate more freely, keeping your pet from overheating and providing a fresh supply of oxygen. ? AIRLINE FRIENDLY- Please check airline regulations before flying. Our carrier easily slides under airplane seats (when wheels are removed) while the expandable space function allows your pet to lay down and relax during your car ride or airplane travels. To assemble: Unfold the fabric pet carrier and lift the sides to assemble. Zip the zippers and the carrier should stand upright. Lift trolley handle up so that it remains upright. Un-velcro the material flaps at the underside of the pet carrier and fold the flaps over the outer bars of the trolley and re-attach the velcro the secure the pet carrier to the trolley. Make sure to unbuckle the buckle at the back of the carrier, wrap in around the bars of the trolley, and re-buckle it to ensure the carrier is secured to the trolley.