The Structure > Objects > Slabs node defines the slabs that you want to add to your catalog and hence to your model. When creating your slabs, there are custom attributes and required attributes. You can add your custom attributes using the Custom Interfaces Sheet sheet (described in the Smart 3D Reference Data).
Before defining slabs, you must define the layers that you plan to use to compose your slabs in the Layers node.
After defining your layers, you define the compositions of your slabs in the Slab Composition node, see Define New Slab Composition Part. When the compositions are defined, you can then define your slabs in the Slab General node, see Define New Slab General Part.