2.5mm magnet balls Mash Speks for stress relief - Speks are like a magnetic putty, without the mess! Due to their 2.5mm size and low flux rating these mini magnets mash around and are oddly satisfying to touch. Build for focus - Need a moment of zen? Build hundreds of super cool geometric shapes with Speks! From the cube to the buckyball, SpeksEd Is your go to resource for step-by-step instructions on building with magnet balls.