■PERFECT SUITABLE FOR: Silver Number 50 foil Mylar balloons are the best choice for: 50th birthday party,50th wedding anniversary celebration,company 50th anniversary party and many other party decoration. ■ PACKAGE CONTENTS: 2 Pieces 40 Inch Silver number Balloons:No.5 Silver number Balloon + No.0 Silver number Balloon + 1 straw. ■CHOOSE THEM: The Silver number balloon is made of high-quality aluminum film that empty balloon is 42 inch,after filled with helium or air,it's 40 inch.Please use the straw in the balloon set to inflate it slowly. ■ TIPS FOR NUMBER BALLOONS: Due to the thermal expansion and contraction characteristics of aluminum foil,please avoid filling more than 90% of air or helium.If it is over-inflated,it can easily cause the balloon to explode at high temperatures.Please avoid leaving the balloons in an outdoor high temperature environment for a long time.If the ambient temperature is too low,it will also cause the balloon to deflate.At this point,you can use the straw in the suit to inflate again,and the balloon will be in perfect condition again. ■SERVICE: We do our best to provide customers with better products. If you have any questions, we promise to give you a satisfactory answer without any delay.