Tovolo Sphere Ice Molds. The innovative and clever design gives you a 2.5" sphere, perfect to accompany your whiskey, scotch, or bourbon. The slow-melting sphere will add a splash of class to your next drink. Each unit neatly stacks on top of another to conserve space while the leak-free silicone cap creates a tight seal, ensuring it won’t tip in the freezer. Made of BPA-free plastic and silicone.