Quantity: 4, Color: White, Material: Sponge.These sponge balls can help you quickly clean scum, grease, lotions, and other residue from pools, hot tubs, spas, and bathtubs, reducing cleaning costs and time. [Upgraded Material] Traditional sponges have large pores and tend to yellow easily. Our descaling balls use upgraded sponge material with a whisker-like surface, making them less susceptible to yellowing. [Resilient and Washable] Our washable oil-absorbing sponges are washable and resilient. After use, you can squeeze the water out of the sponges and rinse them clean. They will quickly return to their original shape for the next use, saving time and money. [Widely Useful] We struggle to remove those unpleasant scum, lotion, and oil stains by hand. These reusable pool filter balls can help you keep your pool and spa clean, eliminating the need for frequent water changes. They can also be used for cleaning bathtubs and other areas.Note: Light reflections and different monitors may cause the color of the item in the image to vary slightly from the actual item. Measurements allow for an error of +/- 1-3 cm.