"Twin Tops" is my rendition of Grand Illusions "Magneturn" (grand-illusions.com). Spinning either top induces motion into the remaining top thanks to magnetics. The design also minimizes rotational friction via opposing magnetics between the Base tower tops and each Top. As combined these features create a great magnetics educational tool. My rendition is larger than the original to make it more "grandkid friendly" (easier to grasp, more difficult to swallow). You will need to purchase 10 neodymium disk magnets 12mm in diameter and 3mm thick in order to complete "Twin Tops". I have purchased these magnets from a local hardware store (Ace) and online (Amazon). Video of prototype is here: https://www.youtube.com/watch?v=woXns1lunyA. Video of Grand Illusions "Magneturn" is here: https://www.youtube.com/watch?v=zllYJokkvV4&t=10s. Designed using Fusion 360, sliced using Cura 2.3.1, and printed on an Ultimaker 3 Extended.