Latex Balloon 30cm - Clear Happy Engagement Medium clear printed latex balloon. Size: 30cm or 12 inches Quantity: 1 Suitable For Air or Helium Inflation. All balloons delivered uninflated. Helium inflation booked in store only. Congratulations on your Engagement. Decorate your celebration with our clear Happy Engagement balloons. Use alone or mix and match with other printed and foil balloons.