The guards (postures) we studied can be found in Meyer’s Rapier, Chapter 3. Here is a brief summary.
Oberhut (High Guard) or Ochs (Ox)
There are two thrusting variants, point forward on the left or the right.
There are three cutting variants. One the left or right with the point back, or Straight High Guard with the point forward.
Underhut (Low Guard)
The Low Guard has the point forward towards the ground. It can appear on either side. It is reminiscent of Olber (Fools Guard) or Wechsel (Changer).
Eisenport (Iron Gate)
This is a low guard for the thrust. The quillons are vertical, like Third in Italian rapier. It can be center, left, or right.
Pflug (Plow)
This is another low guard for the thrust. The quillons are horizontal, like Fourth in Italian rapier. It can be center, left, or right.