I own an old hand held MAC TOOLS auto battery cell tester thingy.I bought it at a pawn shop a bunch of years ago,it's floatin around here somewhere,I haven't played with it in years,I know where my tools are,I just cain't keep up with them good enough.(no puns,please,but if you want to pun,I prefer to pun with the wimmins) It has a needle gage on it and two wires with the metal thingys on it.