The Surface Pro X's Slim Pen charges in your keyboard case
 

Microsoft's extra-slim Surface Pro X doesn't really have a place for a pen on its side, so how do you keep it with you? By tucking it into your keyboard case. The company has unveiled a Slim Pen that tucks into a space on the Type Cover for both stor...

https://www.engadget.com/2019/10/02/...face-slim-pen/