Finally, an easy method for making clear ice balls! Cloudy ice is caused by ice freezing from the outside-in causing air to be trapped within the ice. Clearsphere XL uses a patent-pending directional freezing method to control the direction that water freezes, pushing all the air out of the ice ball. * Makes four (4) 2.5 inch ice spheres * Molds are BPA free and dishwasher safe * Stackable * 6 piece system Includes silicone ice ball mold, insulated freezing chamber, and integrated ice ball storage box.