Transform your party into a dark paradise with our Balloonify Black Mylar Number 4 Balloon. This party balloon is shaped into a number 4 to perfectly pair with other Balloonify letters and numbers to uniquely display meaningful statements. With a durable mylar construction, this foil number balloon is moistureproof and top quality to keep the atmosphere pleasant. You can also reuse this number balloon at countless events. With a self-sealing design, this giant number balloon is simple to use and won't let air escape. Plus, you can inflate this birthday number balloon with a hand pump using air or helium. The aluminum back foil finish compliments all kinds of party decor. Featuring a hanging loop, this big number balloon is perfect for hanging on walls or ceilings for a unique and glamorous addition to your celebration. This foil balloon measures 16 inches in length. To reuse these balloons, gently deflate, properly store, and carefully reinflate without overfilling. Shipped deflated in a 1 count box. This party balloon can be easily inflated with the included straw, providing you with full control to help eliminate the risk of over-inflation. Electric air balloon pump (SKU: RWP1061) sold separately.