In this paper, we establish some results that confirm that \(\sigma \) -normal and \(\sigma \) -permutable subgroups play an important role in the structural analysis of finite groups associated with \(\sigma \) -partitions of the set of all primes. We show that the difference between these two subgroup embedding properties and their corresponding associated classes in the \(\sigma \) -soluble universe is just the Hall \(\sigma \) -structure. Furthermore, we prove that the projectors of every \(\sigma \) -soluble group associated with the saturated formation of all \(\sigma \) -nilpotent groups are conjugate and coincide with the covering subgroups. Some relations between these projectors and the \(\sigma \) -nilpotent and \(\sigma \) -self-normalising subgroups of a \(\sigma \) -soluble group are also exhibited.