s-Modules

In this paper we introduce the notion of *s-modules (s denotes static) as a generalization of *-modules different from *n-modules. The class of *s-modules contains also the class of selfsmall abelian groups faithfully flat over their endomorphism rings. We study characterizations of *s-modules and extend successfully some results in the theory of *-modules. The relations between *s-modules and *n-modules are also considered. Finally we give characterizations of *s-modules with some special properties.