Basic informationMaterial: Aluminum filmSize: 18 inchs (45cm in height)Use occasion: birthdayInflation and DeflationYou can use a straw or a pump to inflate from the inflation port (please note: do not insert the straw too deep, otherwise it may leak). When deflating, insert a straw into the balloon, and then press the balloon to slowly expel the gas, which is convenient for storage and can be used repeatedly.NotesPlease pinch the inflation inlet twice gently to prevent the air leakage.Please do not inflate the balloon to full.Please deflate the balloon a little bit in summer or when the temperature rises due to the thermal expansion and contraction of the gas.Please inflate the balloon on the day of use as helium or hydrogen can float for 6-14 hours.About helium and hydrogenThe balloons can float in the air when inflated with hydrogen or helium. The helium is an inert gas so we highly recommend that you use helium as its much safer than hydrogen, which will explode in the air when there is fire. If you have to use hydrogen, please stay away from the fire.About packaging: There will be creases on the balloon as the aluminum film is folded in the package, but the effect after inflation wont disappoint you.About return: Due to the high cost of postage, we dont provide return or replacement if there is a problem of air leakage or slight color difference, but we will compensate you in other ways.