In this paper, we consider dominating sets D and D such that D and D are disjoint and there exists a perfect matching between them. Let DD m (G) denote the cardinality of smallest such sets D, D in G (provided they exist, otherwise DD m (G) = ∞). This concept was introduced in [Klostermeyer et al., Theory and Application of Graphs, 2017] in the context of studying a certain graph protection problem. We characterize the trees T for which DD m (T ) equals a certain graph protection parameter and for which DD m (T ) = α(T ), where α(G) is the independence number of G. We also further study this parameter in graph products, e.g., by giving bounds for grid graphs, and in graphs of small independence number.