This is a medium with single-scattering SSS, and also absorption. To use this medium you need to create a volume, it will not work correctly on simple surfaces.
You can use it to create true unbiased SSS (although not multiple-scattering yet), using various parameters, including scattering texture, emission texture and various other parameters.
Note that this is single-scattering SSS, not multiple-scattering. It’s much faster than the latter, and much more practical, although it does not allow a few things such as volumetric caustics.
Important: In order for the “ScatteringDefines how fast light gets scattered when traveling through the medium.” node to work, the kernel must be set to “pathtracing” or “pmc” and a node MUST be plugged into the “transmission” pin. Also, “scattering” is only available for “diffuse” and “specular” materials.