These are fun to hold gently in the palm of your hand and watch as the color from the bottom flows upward just like magic. They have chemicals, alcohol, colored dye and are in a glass potion science style container. They start to boil when you grab or hold the end with color in it and watch as it pushes the color potion up through the vial and it boils from the heat of your hand as you watch and entertain yourself as well as others, it gives the sense of magic. These are not meant for young children under the age of 10, and can't be in the sun, heat or too cold of temperatures as the glass will bust. Please use extreme caution as we aren't reliable for any injury obtained from this item. They come in 3 different colors.