Bests & Worsts Reviews from Amazon

The instrument requires that you enter the battery's amp-hours (AH) before the test can start. Automotive batteries sold in the US are rated by cold cranking amps (CCA) rather than AH. There is no reliable way to convert CCA to AH, so it is impossible to even start the test for an automotive battery. The instrument may work on deep-cycle batteries, such as those used in solar systems, as these are rated in AH. My understanding is that automobile batteries sold in Europe and Asia are rated in AH, so the product may work in those countries.