Featuring updated hardware and tilt support, the poppy redSurface PenfromMicrosoftis compatible with select Surface products via Bluetooth 4.0 and provides you with a drawing and writing experience that is similar to using pen and paper. It has 4096 levels of pressure sensitivity with virtually no lag, and can now be used to shade in your drawings as you would with a pencil. There is a tip eraser for a natural workflow, and for more customization options, you can change out the tip to one that fits your style (sold separately). Included is a AAAA battery.