These balloons are going to be a great addition for my grand-daughters 2nd birthday party. I tested one of them out. First there have several colors in the 30 pack, so that is great. You pull the little triangle stopper in the balloon opening out. Once you pull that the little LED light, lights up. From there you can fill the balloon with helium, if you have a tank or regular air. It is stated that the batteries in the light can last from 8-24 hours. I gave the tested balloon to my grand-daughter to play with to see her reaction and of course she would'nt let it go. So she vanished with it and I never say it again, not even when her father brought her back to me. So we will give it at least the 8 hour window of glow to light up the room or sky. It is going to look beautiful floating over Moana! She loves them and that is all that matters and so do I.