Zelta Ice Ball Mold Maker - Silicone Ice Tray - 4 Whiskey Ice Balls - Ice Ball Spheres (Black) Made of leak-proof silicone that won't crack or break, easy to refill. Top mold: 4.7" x 4.7" x 1.06", Bottom mold: 4.7" x 4.7" x 1.92" 2" ball capacity shapes are slower melting than traditional ice cubes Can be stacks neatly in the freezer and keeps refrigerator organized Place the top lid down onto the bottom, inject the water or drink into the hole of the top mold, keep about 0.4" space when injecting water into mold. (It's normal if a little water overflow from mold seam) Dishwasher safe; Wash the mold with hot water before use