Preparing my Mac for sale: deleting/clearing disk in Disk Utility I am preparing to sell my 2012 Macbook Pro, which runs 10.12 (Sierra). I have erased my hard drive using Disk Utility, but am a little confused on where to go next. I'm following this official Apple guide, but my screen shows this:



In Apple's official guide, no disks are listed at the left of the Disk Utility interface. How can I get rid of this disk1 object? Or is this something I need not worry about? Why is this appearing?
That is the recovery image that you reinstall macOS from in recovery mode (assuming you don't have anything else plugged into your Mac).

You can safely ignore it as it is just an installer.

You have wiped the drive. Boot into recovery mode and reinstall macOS. That will have the added benefit of overwriting the disk with new data making recovering your personal data all that more difficult to recover by the next owner.