All, This thing is merely a heavy duty 1 ohm wire-wound resistor. What many vendors of such simple devices don't say is that it will only reduce by 6v. if there is a current of 6a. flowing through it. That current is fairly typical of some 6v radios, but most dash instruments don't draw nearly that much, thus the resistor wouldn't reduce the supply voltage much, and the instruments would be fed too much voltage. A decent solution for dash instruments that are fed through a voltage reducer is one available at NAPA for about $15 (NAPA/Echlin IR-2). It actually does supply a somewhat regulated lower voltage output. I'm using one on my '51 Hudson converted to 12v. Park Waldrop Atlanta C cpe