In this work, a theoretical model for the transmittance in a left-handed metamaterial of different geometries is presented. The proposed unit cells are a combination of conducting wires of rectangular cross-section with square-ring and hexagonal resonators. In this new dielectric compound, dependence of transmittance on the thickness of the resonators are analyzed for the particular case of normal incidence in the GHz range. It is found that the transmittance for the hexagonal resonator shows a significant increase compared to the square geometry resonator.