Features:-Designed for Stanley cups 20oz-40oz, it fits perfectly to the cup wall and provides maximum ice contact area for your drink, allowing you to quickly prepare iced drinks and fully enjoy them.-The mold can make 3 different sizes of hollow ice cubes. The outer diameters of the 1st, 2nd and 3rd hollow cylindrical ice cubes are 2.4", 2.8" and 3.34" respectively. The 1st, 2nd and 3rd ice cubes can be perfectly stacked in a 40oz cup. The 1st and 2nd ice cubes are compatible with 20oz and 30oz cups.-Made of food-grade silicone, BPA free, flexible, with high elasticity so ice cubes can be easily taken out, strong, tear-resistant, and can withstand temperatures from -40°C to +230°C.-Easy to make, just pour water into the ice cube tray,.