About this item 【Impress Your Guests with the 40 inch Number Balloon】Make your birthday celebration extra special with this number balloon. It's perfect for creating a playful backdrop for memorable photoshoots, this adorable number balloons 40 inch is sure to bring smiles to your loved one's face on their special day. Don't let your party be a snooze fest - add some excitement and style with our fantastic black birthday decorations today! 【Helium or Natural Air Both Work Well for this Balloon】This 21 balloon is the ultimate party accessory for 21 years old birthday decorations for girl and boy! You can inflate the 21 balloon number with helium for a floating effect or blow it up with natural air to hang it up as a decoration. Either way, this sturdy black number balloon won't disappoint. It's perfect for long-lasting celebrations that will leave a lasting impression on your guests. 【Radiant Black Elegance】The birthday number balloon feature a vibrant, luminous black hue that exudes timeless elegance and creates an enchanting focal point at birthday parties and anniversaries. Their gleaming opulence bathes your event in warm, lavish ambiance, ensuring they become an indelible part of your cherished black memories. Elevate your occasion with these dazzling 21 birthday balloon, perfect for birthdays and anniversaries, that deserve a touch of resplendent brilliance. 【Save Time and Effort with a Balloon that Self-Seals and Reusable】You could manually use your mouth on the straw with natural air to inflate or deflate the 21 number balloon. Just simply locate the end with arrow tab, pull the number 21 balloon open, and use the straw to blow air into the black number balloon until it's 90% fully inflated. After the party, deflate the 21st birthday decorations for girl or boy by opening the tab and using a long straw to release the air.