This node can be added to pairs. It prescribes that the temperature field is continuous across the pair. Continuity is only suitable for pairs where the boundaries match.

If this node is selected from the Pairs menu, then from the Pairs list, choose From list (the default), All, All contact pairs, or All identity pairs. If you choose From list, select the pairs where you want to impose continuity across the pair boundaries by clicking the Add button () and choose the pairs to add from the list in the Add dialog that opens; then click OK. A pair has to be created first. See Identity, Contact, and Sector Symmetry Pairs for more details.

Physics Tab with interface as Heat Transfer in Solids, Heat Transfer in Fluids, or Heat Transfer in Solids and Fluids selected: