LED Display Cigarette Lighter Electric Voltage Meter for Auto Battery (DC 12/24V)

Pros: Allows you to monitor battery condition and charge rate of alternator.
Early warning of battery losing charge too quickly before it becomes an issue on a cold wet morning, never happens on a bright sunny day outside a garage.

Cons: It rattles ! suggesting no real quality control.
Changes voltage display very quickly, rather than a smooth average read.

Other: If you like gadgets and don't like being caught out with a flat battery it is good value for the money, shame they never just took a little more care in assembly to stop internal rattle.

Pros: - Easy to use - It works - It is not to big

Cons: - Not very accurate, the voltage keeps going up and down. They should have used an average voltage.

Other: Good product, but nothing special and not very accurate. The voltage changes all the time (not big differences) so if you need a very accurate reading this is not a product you should buy. But it does the job for me because I just have to know my battery doesn't go under 11,4 volt.

Pros: It allows me to monitor the voltage in my trailer without using a multimeter. I just plug this device in the 12V power outlet. It is that simple to use. I have only praise for this simple to use product.

Cons: None. I have no disparaging remarks to make about this simple to use product.

Other: This is a simple device and requires only a simple review. It is quite simply easy to use. As long as the build quality hold I will be happy.

Pros: Very very useful !!!

Cons: Tragically unstable information on display. Display filter is not correctly attached to the body and it seems too transparent.

Other: Although I`ve written more cons than pros this voltmeter is really good helper. Absolutely I recommand.

Pros: ??? ???? ???????? ????? ?? ????????. ???????? ???????? ?????.

Cons: The measurement accuracy could be higher. Deviation 0.4v, but it's good enough. Red characters under blue filter - not a good solution. Filter is better to make a dark red color.
LED is bright enough, measure accurately. The case is assembled well.
Inside is a stabilizer that allows the device to operate over a wide range of supply voltage. I have worked on and 5v to 30v (12v deviation was 0.2%)

Other: The perfect solution for this price. Even some digital meters (without housing) is considerably more expensive. This simple and accurate. Can be used in addition to the basic structures of amateur radio purposes, such as regulated power supplies.

Pros: Does what it's supposed to do, namely measure battery voltage, and display it on the LED display.
Easy to use, just plug in and play.
Is readable in sunshine, and bright at night!

Cons: The cover is blue, but the LEDs are red. THey could have made it in blue leds for a nicer looks.
Not very sturdy built! Plastic housing will do the job, just don't throw it to the floor in an outburst of anger, or the device won't survive.

Other: If you like gauges on your dashboard, this is one unit you should install too!
It adds to the fancyness of your car, though it may not be very useful.

Pros: A very good gadget to have for anyone with an old car, especially if you live somewhere cold like me.
Looks cool, fits snugly in the cigarette lighter socket.

Cons: The rattle that some reviewers reported was there on mine too. The loose part was the plastic covering the display, easily fixed by a drop of glue.

Other: Read this right, and you'll know when it's time to charge or change the battery.

Pros: To monitor battery condition and charge rate of alternator.
Early warning of battery losing charge too quickly before it becomes an issue on a cold and wet morning, never happens on a bright sunny day.

Cons: Too big in size and fixed a position. Prefer smaller in size and can move up and down.

Other: Good value for money rather than caught and stuck with a non moving car.
If you like gadgets and don't like being caught out with a flat battery it is good value for the money.

Pros: Extremely useful gadget, especialy at winter. Well built, good quality and refresh rate. Very bright - can see the values even on sunny day.
Very helpful if you have an old car (or the Russian one =) )

Cons: It will be extremely good to implement the On/OFF button. My cigaret lighter is allways ON, so I have to plug/unplug the device not to kill the battery.
But actualy it is not even a Con, I'll made this switch myself.

Other: Best product for its price. Very accurate measurment, well built and nice looking. I recomend this for all Russian car owners. the thing you must have on you vehicle

Pros: Very easy to use. Very good to monitoring the charge of alternator and the voltage of the battery before start the engine. The accurate is good. I have compared with a laboratory voltmeter.

Cons: There is a fault in the reading of the voltage. The voltmeter can't display 11.9V! When you increase the voltage with a variable supply, the display goes directly from 11.8V to 12.0V. I have seen this problem on two items, so I think all the items have this fault !

Other: Nice price for this gadget.