This item: Genuine 925 Sterling Silver Letter Beads Initial A-z Dangle Alphabet Crystal Charm Fits European Bracelet Necklace ( Letter A ) £9.90 £ 9 . 90 Get it as soon as Thursday, May 29 They are derived from two-dimensional curves that were put into use by the 19th-century German engineer Franz Reuleaux. These sculptures roll with pleasantly unintuitive smoothness, inspiring mindfulness and creativity in people of all ages. These solid of constant width are the perfect desktop toys for your office desk. Roloids are non-spherical solids that amazingly have constant width in every direction—allowing them to roll smoothly. Made from solid copper, stainless steel, and brass (one of each in the 3-pack). They are kinetic desk toys made of metal, one copper, one brass, one steel. USB C Fast Charger, 3 Pack 20W USB-C Power Adapter with 3 Solids Of Constant Width The Ultimate Solid Of Constant Width Steel - Matter Collection Roloids Solids Of Constant Width 3-pack 1 Artistic, geometric solids that roll as smoothly as spheres. As intriguing to the artist as they are to the mathematician, Roloids are based on two-dimensional curves with incredible mathematical and aesthetic properties. Similar to Eulers disc. Ova News Ovulation Detection Kit Fro Prega News Identifies 5... These cool desk gadgets can also double as fidget toys or decorative balls. They can be used as home decor or coffee table decor or be put in a bowl as decorative bowl fillers. Perfect for artists, scientists, teachers, learners, and anyone who appreciates wonder in simplicity.