Which SurfaceAppearance Properties Do These Belong To?

I decided to play around with SurfaceAppearance and its properties to see how it works out, so I ended up searching up for some free meshes with interesting PBR Textures and such. After reading the basic introduction of the Class on the Roblox Dev Hub, I was still not able to assign the following to one of the 4 Properties of SurfaceAppearance.

Which ones do they belong to?

Diffuse

image

Lightmap

image

Diffuse belong to color map. But there is no light map.