Extend the length of your monitor cable with these high quality units from. These 15-Pin Monitor cables are connected to standard monitor cables to extend the cord length between your computer's video card and the monitor / projector output. With Ferrites. Ferrites are homogeneous ceramic materials composed of various oxides (Iron Oxide). Ferrites exhibit high magnetic permeability and high electrical resistivity. This means that they limit the amount of current flow and thus can exhibit very low energy losses. This allows the device/cable to be highly efficient with minimal losses. This also allows devices to function at much higher frequencies.