debian-installer/tools/kbd-chooser/debian/keyboard-at.templates
Template: kbd-chooser/kbd/at Type: text _Description: PC-style (AT connector) keyboard
Technically, there are two possible PC-style connectors. The AT connector is a large round plug; the PS-2 connector is a small round plug. They contain the same set of wires, but they're physically different. (I actually have an adapter connecting the PS-2 plug on my computer to the AT plug on my keyboard.)
Manufacturers will generally mention only the one they supply in their hardware specs, so this may confuse a cautious person who has a PS-2 connector on their system.
Better description here would be PC-style (AT or PS-2 connector) keyboard