The set includes:(1) 30"/76cm high x 22"/56cm wide Hello Kitty Pink and Purple Large Mylar Balloon(2) 18" Hello Kitty Pink Flower Shaped Happy Birthday Mylar Balloons(2) 18" Plain Lilac Purple Star Mylar BalloonsThey are not filled, you can fill at your local store, or rent a helium tank from your local party store or welding company. You can also air fill it and tape to the wall or attach balloon sticks. Please note that mylar balloons last about 1-2 weeks when inflated, although actual float time varies.