4.8A 24W Dual USB Car Charger Volt Meter Car Battery Monitor with LED Voltage & Amps Display in Red LED, Cigarette Lighter Voltage Meter, Compatible with iPhone 15 Pro Max Samsung Galaxy S24

We tried both colors. Red is easier to see than blue in daylight. Accuracy should be checked with your own voltmeter since we noticed a 0.2 V difference between units.

I originally bought this item in the blue-colored display, as I favored that color. I bought it to use in our aircraft, hoping that it would be able to keep my iPad Pro 10.5 (with bluetooth, wi-fi, and cellular capabilities) fully charged during use of the iPad as a backup device that displays navigation, traffic, and weather while inflight. I LOVE the capabilities of the iPad for aviation use, but on sunny days at full display brightness, other chargers I have used could not keep it charged. That meant that, on long flights, I was always concerned about the battery dying and losing those tremendous backup capabilities.Well, the Jebsens charger was absolutely up to the task, never allowing the battery in my iPad Pro to drop below about 95%, usually keeping it at 100%. When flying with another pilot friend, it also kept his iPad just as fully charged at the same time as mine... FANTASTIC!!! In addition, it also provides a digital LED display accurately showing the aircraft's charging system voltage, which is a real plus considering the rather poor performance of the analog gauges on most legacy general aviation aircraft. I know that it is accurate because I checked it against two other very high quality voltmeters from different electrical test equipment manufacturers whose displays always agree to within hundredth of a volt, and the Jebsens unit was never off by more than .1 volts from the other two. It also displays the charging rate for any device to which you have it connected to quickly let you know that status.However, although I was tremendously pleased with its charging performance and system voltage display capability, the light intensity of the blue display was incredibly weak, making that display virtually unreadable in any daylight. I hoped it was just a fluke, and that I simply got a unit with an abnormally weak display. I contacted Jebsens about the problem, asking if what I was experiencing was normal and, if not, could I possibly exchange it for another unit. I also asked that, If the weak display was normal, could I exchange the blue display unit for a unit with the red-orange display, hoping that it would be brighter.They responded very quickly, basically telling me that the blue display was weaker, and that they would definitely send me a replacement unit with the red-orange display at no cost, and that I could just keep the original unit as well. What GREAT customer service!!!When I got the replacement unit with the red-orange display, I found that it performed just as well as the blue display unit, but that the intensity of the display seemed about three times as bright as the blue unit. In extremely bright sunlight it is still a wee bit of a challenge to read it, but it is more than acceptable.I have been SO happy with the replacement red-orange display unit that I just bought another one to give to my pilot buddy who had used mine along with me previously. I am also using the original blue unit in my Toyota 4Runner that is my off-roading, trailer towing, vacation vehicle. With its heavily tinted windows, the blue display unit is at least usable.So, if you intend to use one of these chargers during the day, I would STRONGLY RECOMMEND buying the red-orange display unit. However, no matter which one you choose, you'll get GREAT performance from a GREAT, responsive Seller, at a GREAT price when considering its capabilities... especially keeping high-draw electronics very well charged in your aircraft, boat, or road or off-road vehicle.

Was having a huge problem with my boat batteries being dead on arrival at the boat ramp at launch time. They would be so discharged that a jump box couldn’t even bring it back to life and I’d need to take it home. I store the boat in a lot with no power, so I tried so many elaborate procedures and try and pick up the boat a day before and try and charge overnight and test fire the morning before a trip, but i would frequently forget a step and end up with a dead boat and a car load of kids. So I finally got this phone charger with voltmeter to quickly and accurately give me a reading, along with a battery kill switch and a backup battery. I didn’t trust the built in voltmeter in the dash of the boat because it would read much lower than my handheld volt meter at the batteries, and the dash voltmeter gauge had way too large a range. 12.9 is a full battery with engine off, 13.3v with engine and alternator running, and 12.3v is probably lowest voltage to start a 4.3l v6 engine. My analog dash gauge range is from 10v-16v and it is hard to read such a small working range of 12.3-12.9v.With this usb 12v USB duel charger I can quickly and accurately read the voltage of the battery system, on the trailer, at the ramp, while underway and at anchor with the stereo blaring. It is bright enough to read in direct sunlight, which is super important. Be sure to get this color led, as other colors may not be bright enough.I did learn that the readings at my dash with this device are 0.6v lower than at the battery. This is logical, As there must be a voltage drop through the wiring and fuse panel. So a full battery reads 12.6v through this device and I can still start the boat when it reads 11.8v. I have confirmed the accuracy with a reputable handheld volt meterBecause the 12v socket and my stereo are always on and not tied to the ignition, I can leave this plugged in all the time and get a bright red reading from the device to let me know the kill switch is not off and to remind me to kill the power before storage (so the stereo won’t kill one of the batteries)It also does a great job of charging my iPhone 12 pro max and iPhone 7 max simultaneously and with enough juice to allow me to run navigation on a phone at full brightness constantly and still charge the both phone while also streaming Bluetooth to the stereo on the other phone. (Pic shows phone mounted on steering wheel, which partially blocks view of charger display)

The light is to dim in daylight.

It works!

I use this on my ocean boat to make sure my batteries aren’t draining. Very convenient to glance at the plug and see how many volts my batteries are at. Highly recommend

I bought this as a quick and temporary means to keep an eye on my voltage as I upgraded my car audio system and wiring. Seems to be accurate within a tenth of a volt. The numbers are well lit and easy to see day or night and the charging ports work for my cell phone and quickly charges. Wouldn't hesitate to purchase again. Worth the money.

I BOUGHT ONE FOR ME and I liked it so much that I bought another one Jebsens 4.8A 24W Dual USB Car Charger Volt Meter Car Battery Monitor with LED Voltage, for my wife's car.