Bests & Worsts Reviews from Amazon

The picture on Amazon site is not correct. This battery monitor shows the voltage value with .01 precision (or two digits after decimal point). That is far more then enough to tell the battery status. I put it in the car, it automatically switches between "battery status monitoring" and "charging status monitoring". When the engine is stopped, it is in "battery status monitoring mode", when engine is running, it will be in "charging status monitoring" mode. Amazon's price is even better then Walmart. Definitely a great value buy. Will recommend this item to my friends. --- Update --- Amazon has updated the new photo for the product. The picture is correct now. --- Update 5/30/2016 --- Lately, my wife's car won't start. I plug in this battery-Charging System monitor and turn on the power. The monitor shows 11.65V. Right there, I know something is wrong either with the battery by itself or the car's charging system. At this voltage level, the battery won't have sufficient power to crank up the engine. A typical reading before turning engine on should be around 12.34V. Nevertheless, I replace the old battery with a new one. The monitor now shows 12.30V when I turn on power. I drive around with the battery-Charging system monitor plugged in. I see voltage level is at 14.34V. That's good. This means the charging system is charging the battery. After driving around for about 15 minutes. I turn off engine. The monitor now shows battery is at 12.74V (higher then the initial 12.30V) . This confirms the new battery is taking charge from the charging system when I drive the car around. This battery-charging system monitor makes it easier to figure out if the battery goes bad or the charging system is not working correctly. Most mechanic will ask for a $120 diagnostic fee to figure out what is going on first, then additional charge for fixing the problem. I just save myself $120 diagnostic fee with this battery-charging system monitor.