Service menu to write ISO images to USB driver using "isoimagewriter", the new tool by Jonathan Riddell. At the moment (August 2017) is still in alpha and distributions still don't provide it.
Wiki page: https://community.kde.org/ISOImageWriter
The source is here: https://cgit.kde.org/isoimagewriter.git/
and the builds here: https://download.kde.org/unstable/isoimagewriter/