One other thing. If your LunaPro was manufactured prior to late 70's--early 80's, then it was made to use mercury batteries. It won't work right with the alkaline replacement batteries even though the battery number is the same. The alkaline batteries do not have the stable voltage that mercury provides, and the alkaline are 1.5 volts, compared to the 1.35 of mercury. Bogen makes an adapter that comes with batteries for somewhere if the range of 25 to 30 bucks. It seems that a lot of folks on ebay aren't aware of the conversion adapter, and sell off their LunaPros when they put in new batteries and the needle starts to bounce around.
Bill