Polymer snow is made of tiny white grains of a special hydrophilic (water-loving) polymer. Just add water and the polymer grains will absorb the water molecules by osmosis and increase to 100 times their original size! If you use distilled water to hydrate the snow, as the water evaporates, the snow will shrink to its original size, ready to use again. Create your own winter wonderland in just a few seconds! Snow comes in a 5.5" plastic test tube. About 17 g.