When we introduced the new Ultraslim Plus Wireless Keyboard, people started to ask questions about how to switch multimedia function keys in the 6th row to standard legacy F1-F12 keys. This topic was mentioned several times on our Lenovo forum article and support article where you will be able to find a solution. We recommend that you use the Lenovo driver and that way you will not only be able to switch your function keys, but you will also have a battery life indicator for your keyboard and mouse.
The same question about the Slim USB Keyboard is asked when our customers buy the Edge desktop. It is difficult to find, but a driver is preloaded for this keyboard and you can download it on the website using the following driver. Once the driver is installed, you will then find a small app in the Start menu in order to make the switch between multimedia keys and legacy F1-F12 keys.