- ? ? Material: Aluminum Foil - ? ? These Vehicles balloons can be filled with hydrogen or helium for walking effect; - ? ? If you use air they will not float. All the balloons are double-sided. - ? ? The cute transportation balloons ideal for your boys or girls?s birthday party celebration decorations or surprise gift. - ? ?Warm tips? 1. To foil balloon must be inflated slowly can pump to 70%-80% and then use a straw to blow easy to control volume in order to avoid bursting. 2.If there is a case of two layers of aluminum foil sticky encounter be sure to stop inflation gently pulled the hand (in) two layers of aluminum foil and then inflated or(otherwise) easily damaged. 3. Sharp objects/not clean ground/direct sunlight and excessive extrusion are easy to get the ball skin damage burst. 4. Please inflate these balloons on the same day you need to use them one time inflating of hydrogen or hellium usually keeps balloons floating about 6-14 hours.