Several lumped element-based epsilon-negative (ENG), mu-negative (MNG), and double-negative (DNG) metamaterial designs have been developed for operation at 400 MHz in the UHF frequency band. The use of lumped elements enabled the creation of highly sub-wavelength unit cells whose overall size was λ0 /d∼75 at 400 MHz. The measured negative index material (NIM) showed an effective real index of refraction nreal =-3.11 with a total loss that was less than 1 dB/cm. The NIM bandwidth was >10% in the neighborhood of 400 MHz. © 2008 American Institute of Physics.