Luxury Ice Sphere Molds By Jack Harrison - Top Quality Silicone - 100% Lifetime Guarantee - Pack of Four Pack of Four Silicone Ice Sphere (2.5") Molds. Top Quality by Jack Harrison. Super easy to clean, use and store. These are ideal for both home and bar use! Fully reusable, make millions of ice spheres! Since they're made with top quality silicone they come with Jack's Personal Lifetime Guarantee (see below)! An excellent gift idea.