Following a bp of battery on a car, I bought 3 of these items for less than 8 euros. The first gave a measure fluctuating from 11 to 15.5 volts, even varying engine off (battery alone). I tried the other 2 in several cars, only 1 result seems reliable, the other 2 fluctuate constantly. The price of the result is 3 times more expensive, Qty waste made in Rpc. A voice coil with an LED diode to illuminate the display on a 10-15 Volts amplitude would have been simple, readable and effective. At least one works, but ...
