I just started goofing off with Kali Linux (metasploit against a metasploitable image) and had installed it to virtualbox. I tried to install Guest Additions so as to be able to make the screen match my actual monitor and allow for fullscreening. In trying to do that, I was told I needed kernel headers for the 4.7 kernel, but the Kali I just installed (2016.2 version) was running on the 4.