Review on 🎈 UltimateBunch Balloons: Instant Self-Sealing Complete Set by Steve Griffin

They work great. I've filled about 300 of these without losing a single filling and they've all held water for well over two hours. I would suggest using an ice box or small water bath to fill. The ice chest on wheels allows you to place multiple balloons in strategic locations. About 1/4 to 1/3 filling of the ice box with water is of great importance for the survival of the balloons. Start by putting a plastic ring on the hose and then dip the unfilled balloons in water from the ice box. If they start to fill up and fill up slower than you feel, you can lift the bundle in and out of the water, much like you brew tea, and they'll fall into the water in an orderly fashion in an ice box. Don't overfill them. We used it for a balloon slingshot and shot it 100 meters.