The Boundary Multiphysics Coupling node () defines a coupling feature that can only exist (have selections) on the boundary geometric entity level of the current space dimension, which represents surfaces in 3D, lines in 2D, and points in 1D.

To add the Boundary Multiphysics Coupling node, under Building Blocks, right-click the Multiphysics Couplings branch node to add this from the context menu. You can right-click the Boundary Multiphysics Coupling node to add many features.

The Settings window is almost identical to the Generic Multiphysics Coupling node, except that it does not include the Supported geometric entity levels list.