In the glyptic repertoire of roman-republican age, numerous subjects that must be recognized as amulets with probaskanica function. These objects are designed to protect the owner from the negative effects of the evil eye. The ridiculous and caricatural aspect often seen in these engraved gems characterized the grotesque and/or deformed beings such as hunchbacks, bald, dwarfs, pygmies. A further common typical element is the sexual hypertrophy, another characteristic that, in literature, has always been associated with a clear apotropaic function. From a functional perspective, all these features would contribute to identify these characters as useful expedients to ward off the charm. Instead, from a perspective of antithetical analogy, they communicate positive symbolic concepts, such as the fullness of life, fertility, rebirth and victory over death. Thanks to the analytical study of some pictures engraved in gems conducted by the authors, it has been possible to define a singular set similar for style, subject and type of material, produced between the second and first century BC in the Italian peninsula. The paper intends to explain the figurative and material elements, both constant or variable, that contribute to reinforce the symbolic and amuletic meaning of these gems.