Note that hydrogen can't be used indoors or in crowded places. There have been many newscasters who said that hydrogen balloons were used in weddings and ceremonies, and smokers' balloons exploded, so the law has stipulated that hydrogen cannot be used in celebrations and public places. I used to do wedding planning service in Guangzhou. If you want to have a floating balloon at the wedding, you can use helium. Now it is used in general celebration occasions. Although the price is a little high, for an important day in our lives, friends and relatives come to bless us, and safety is the most important thing. You can find some wedding service companies to help you operate. It's not cost-effective to go directly to the gas supply company, because they usually only provide gas. You have to find someone to inflate it on the spot, and the price of a bottle of gas is not low. Plus the freight, it's best for the wedding company to help you operate it, so you can be a happy new person that day. One more thing must be noted. If you find a wedding service company, you must specify helium in the contract with the wedding company, because some companies in the industry will use hydrogen in order to earn more money and cheat new people!