Happy Birthday Cake Shape Kids Birthday Chiller Party Theme Decoration Foil Balloons Pink Pack of 5 Pcs Make your little one's birthday party even more special with our Happy Birthday Cake Shape Foil Balloons! Perfect for party decorations, these balloons come in a pack of 5 and feature a cute pink design. Add a touch of celebration to any room with these fun and festive decorations. Floating Time (Helium)The foil balloons, filled with helium, will stay full for 2-5 days. They may float for longer but will start to appear more deflated as they lose helium.