I am hoping you are here because you know what you want, and you know what you are looking at!
I used this KVM with my home PC, my home laptop dock and my work laptop dock.  It worked well, but I have now changed my setup.
The KVM comes complete with all the cables to connect to the four computers you would like to control.  There are sockets for keyboard, mouse, two monitors, a set of speakers and a microphone and two switched USB devices.
Some important things you should know: - I do not have the cover for the back of the device - I do not have the flash upgrade cable for the device (looks like a RJ45 networks cable on the KVM end) - I believe the KVM is configured for a european keyboard standard.  This means some UK keyboard keystrokes were not passed correctly.  I was able to work around that by using ALT-codes to enter the troublesome characters.  For example, I remember \ was one of the characters affected, and could be typed by holding ALT, typing 92, then releasing ALT. - I believe the flash upgrade cable is required to change the keyboard layout if that is something you would want to do - The power supply has a european plug, but an adapter is supplied.  I used the KVM with the adapter for many years without issue.
The device was excellent for my use. I am happy to answer any questions you might have.  I hope this device is useful to someone.