Wow!!!! just wow! Bought these for my son but wanted to keep them for myself, everyone has been playing with them. I filled 2 large bowls up (careful to not put too many in as they expand a lot) I still have 3/4 of the bottle left! They also last filled for days, before decreasing in size again, waiting to be watered again. My son has autism and he loves them, they are a great sensory tool. They have been played with day after day and they are likened to "Obies?" my son calls them (youtubers use them all the time apparently). Fantastic price for what they are, would buy for any age, even my grandparents as you can also use them to keep plants watered.