Set of 4 dryer balls, made from all natural wool fibers from our herd of sheep. Dryer balls save energy by reducing drying time (The fibers absorb moisture from the clothing.) They also replace throw away dryer sheets. If a scent is desired, a few drops of essential oils (not included) may be added to each dryer ball. To use, put all 4 balls in the dryer. Dryer balls can be used repeatedly for about a year. Dryer balls come in your choice of either white or brown. Both are the natural coloring of our sheep, so neither color is dyed nor will bleed into clothing.