In this paper, we investigate a new subclass of H-matrices, termed weakly \(SDD_1^\dagger \) (for shortly, \(WSDD_1^\dagger \) ) matrices, and explore the relationships between \(WSDD_1^\dagger \) matrices and other subclasses of H-matrices. Based on the algebraic properties of \(WSDD_1^\dagger \) matrices, the infinity norm upper bound for the inverse of \(WSDD_1^\dagger \) matrices is established, and several sufficient conditions are provided to ensure that the k-subdirect sum of two \(WSDD_1^\dagger \) matrices still belongs to the same matrix class. Furthermore, numerical examples are presented to illustrate the corresponding results.