6 ft / 72 Inch Giant Jumbo Round Latex Climb-in Balloon (Premium Quality), Pack of 1, Yellow The opening of the balloon is 8 cm wide. Fully inflated, this balloon contains 3.2 cubic meter of air or Helium corresponding to 3,200 liters. Tensile strength if filled with helium, is 6000 gram. It is best to inflate this balloon with an electric balloon pump. The balloon can best be closed with an 15 cm clip. Shipped uninflated. Can be air filled or helium filled