Have you ever seen such a small mattress? Of course it's not for sleeping, and I guess even the dwarfs in Snow White don't need it. And it's not for pets either. So what is it for? Is it just a toy for little girls? Of course not. Think about it, don't many people have the habit of hiding some valuable things inside the mattress? That's right, this mini mattress serves the same purpose. If you have some private savings, whether it's paper money, coins, or other small items, you can hide them in this hollow mattress. So it's like a mattress wallet, and I bet no one would think of using it to hide things. Though it's small, it's not cheap.