One face of an imported CAD part, with its surface parameterization: a face of a body, or a surface saved as STEP (the part's Faces). Where a Solid is taken it counts as the half-space on the side opposite its normals — cut or intersect with it, or give it a thickness with Thicken Surface; it also drives Cell Grid on Surface.
Which face: a reference into a CAD Body's faces. Pick a face in the viewport to create one.
Values the block gives besides its output. The editor lists them under Properties, and an input can read one by reference.
The half-space on the side opposite the face's normals, as a Solid: the exact distance to the face, negative behind it. Cut or Intersect with it; where a Solid is taken the face counts as this by itself.
The signed distance to the face, negative on the side opposite its normals; give it a thickness with Thicken Surface or drive a Range Map.
The axis-aligned extent of the face's triangles.
This face in a list of one, like every value that has a list type.
The body that contains this face.