Surprise your birthday girl or boy by displaying a sweet "Happy Birthday" sign with our Balloonify Silver Mylar Letter C Balloon. Designed in the letter C shape, this metallic balloon can be matched with other Balloonify number or letter balloons. This letter balloon is made of mylar, giving it moistureproof properties to last longer, even in humid conditions. The durability of this mylar balloon ensures that it is reusable time and time again. To avoid the air from leaking out, this birthday balloon comes with a self-sealing design. Inflate this custom balloon with air using a hand pump or helium using an automatic pump to be party ready in seconds. The aluminum silver foil finish of this party balloon accentuates your celebration decor by giving it a shine to it. Built-in with hanging loops, this graduation balloon allows you to hang it on a wall. This foil balloon measures 16 inches in length. To reuse this balloon, 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) is available and sold separately.