This scientific area has attracted much interest due to its potential to write small magnetic elements with a low - power electric field rather than magnetic fields that require high - power charge currents. (uni-mainz.de)
The tips (see image below) are comparable to the probes of an atomic force microscope and can be moved across magnetic elements of inorganic or biological materials with high precision. (sciencedaily.com)
It's IP54 dust and water resistant (and sweat proof, apparently) and with magnetic elements in the earbuds it can also become a «fashionable necklace accessory.» (androidcentral.com)