The Tovolo Sphere Clear Ice System makes four crystal-clear 2.5-inch ice spheres at home. The secret is directional freezing. Foam insulation slows the freeze and sends it from the bottom up, pushing air bubbles and impurities out before they become trapped in the ice. To use it, fill the center tube with filtered water, let it flow into the four silicone molds through the base holes, and freeze for 12 to 16 hours. The flexible, BPA-free silicone peels away for a clean release with no cracking or prying. Large clear spheres melt more slowly than standard cubes, so whiskey, bourbon, scotch and cocktails stay cold without watering down. Assembled, the system measures 15 by 4.75 by 4.5 inches. The silicone molds are dishwasher safe. Hand wash the foam tray and fill tube in warm, soapy water.
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