The neodymium NIB magnet spheres are ultra strong rare-earth magnets and perfect pieces for DIY projects and for building 3D puzzles out of magnets. Their strong magnetic properties allow them to shaped molded torn apart and snapped back together in unlimited ways kind of like metallic silly putty. What you do and create with them is up to you or just use them as a stress reliever. - 3mm diameter uniformly sized spheres - Note : pictures shows neodymium shperes in various sizes. This product is for 3mm spheres. - Ultra strong rare-earth magnets - Perfect pieces for DIY projects and for building 3D puzzles out of magnets