Nintendo Wii memory

I have an older Nintendo Wii that I would like to sell. Before I can list it, I’d like to include how much memory the console has. I searched Nintendo support and they said I could see this under Data Management. However, when I go into that area, where the installed games are shown, I see "693 Blocks". What does that mean? Is there a different way I should use to determine how much memory the console has?