This cable lets you charge your Surface Pro or Laptop from a USB-C battery
https://www.theverge.com/2018/12/18/18146395/j-go-surface-connect-usbc-charging-surface-pro-laptop-cable-battery-microsoft
Earlier this year, I wrote about the long-awaited Surface USB-C adapter that finally added a versatile USB-C port to Microsoft’s Surface Pro and Surface Laptop computers. The adapter works as advertised, but it’s large, heavy, clumsy, and expensive. I outlined three ways that Microsoft could have designed a better cable, hoping that the company would listen.
Turns out, someone was listening to at least one of those suggestions because you can now purchase a cable that lets you directly connect a Surface Pro or Surface Laptop to a USB-C battery or wall adapter for charging. The J-Go Surface Connect to USB-C Charging cable costs $19.99 and is available to order now.