Lenovo ThinkPad 45N2630 Digitizer Stylus Pen.
Lenovo Active Pen 2, 4096 Levels of Pressure Sensitivity, Customized Shortcut Buttons, for ThinkPad X1 Tablet Gen 2, Miix 720, 510, 520, Yoga 720, 920, Replacement Tips Included, GX80N0782