LIHAN 3 USB Car Charger,12V/24V Voltage Meter, QC3.0 Output 4.8A, Cigarette Lighter Plug Adapter Compatible with iPhone,iPad, Samsung, USB Charging Devices, Silver

This thing is amazing. To any that have been waiting on super slow charging, get this. My iPhone charges in about 30 mins as it does max depending on device and will display how much is being applied. The battery voltage is a nice touch too if you don't have anything plugged in. However this is only going to be an accurate read before you start your vehicle. After that it's going to be showing the power your alternator is putting out. So, either way it's a good way to monitor your vehicles charging capacity.

I've used this to measure battery health, and it's proven fairly accurate. I wouldn't trust it as a savior, but it's a nice tool to warn of impending doom, while charging my phone. I will say I don't leave it plugged in overnight, since most power sources I know stay hot with the ignition off (fear of battery discharge). But if you're fine unplugging and tossing in a cubby when you shut the car down, it's heaps better than a simpler charger at the same price.

I like the look and possibility to choose color of the charger head, I'm my case red which blend with my car's displays. Unfortunately color of voltage reading display has only one color: blue.My cigarette lighter powers up when I turn the key to accept and then it take couple of seconds for display to show battery voltage. The first number shown is pretty accurate (I checked with volt meter direct on battery), but then it starts to fall down quickly for some unknown reason (it goes from 12.7 down to 12.0 by 0.1 increments). Since I know that first reading is accurate that's ok with me to know battery health. After car is started voltage jumps to 14 to show charging voltage which is also accurate. The first reading (static battery voltage ) may not work well with modern push start button cars, or those that have always power on on cigarette lighter for above mentioned reason.As for phone charging it works fine as basic charger.My phone has fast charging capability and I tested charging amperage as 1.41 wats which is below advertised, but good enough for me.

This little 12/24 volt adapter with 2 USB ports is well worth the money. If you're like me, your car has no voltmeter so you're only aware of battery or alternator trouble when you see a warning light on the dash... which by then is too late. This handy device will not only charge up to two devices, but will show you how many amps are being pulled from the battery while doing so. And when nothing is charging it displays how many volts your battery is currently operating at. And because of its short plug length, it doesn't stick out of your outlet like a lot of dual or triple USB adapters. In fact, it only ends up protruding one quarter of an inch from my dash. (Your results may vary depending on your car's interior design.)No matter how well it fits, for $10, its a steal for two USB ports, a voltmeter, and an ammeter all wrapped in a simple, sleek, shiny black adapter with a handy little digital display. Far more than you get with most of your basic 12/24v USB adapters.

Do not use the green plug unless you have a device that can specifically use it. Most everything is designed for 5 volts and not more than 2.4 amps charging. The green pin charges faster because it varies the voltage from 9 volts down to 1 volt. My Samsung S9 cell phone worked just fine until I tried it on the green pin. Now it is toast - the display is dead, but it still vibrates.

I’m pretty happy with this. I’ve had it for a few months and it’s been very accurate. I have two other digital displays and a dmm and they are all within a tenth of a point from each other. It also reads out the correct voltage from your phone. The blue light is not distracting at all, which is nice. The fit is almost perfect enough for me to shut my cigarette door with it still plugged in on my Lexus, but not quite. I like how it’s fastened pretty securely, and it takes a little effort to get it out. The USB ports also are still snug after three months of almost daily use.Couldn’t be happier with this.

Great product after a few weeks of heavy use. It is compact enough to fit into the cigarette lighter recess in the ashtray compartment of my European cars. The display is bright enough to be seen in sunlight, unlike a similar adapter I purchased of Amazon( also purchased a charger that is square in shape to see with integrates better into the center console area of the dash), The display is not too bright at night due to the compact size. I like that I am able to monitor the charging rate of the phone or tablet and as a result was even able to identify charging-cables not supporting "fast charge".The fit and finish is far better than most other products I own. Very satisfied.

It charges all of our iPhones pretty fast. I bought two almost a year ago in the silver color option for our two family vehicles and had zero issues with them, and the shape of the charging port and the digital screen design is pretty nice looking.I recently purchased a new vehicle and wanted another one of these and decided to go with red to match the dark orange trim of the vehicle. The color is beautiful and almost an absolute match with my "Go-Mango!" (Orange) 2006 Dodge Charger Daytona R/T.Absolutely will purchase again for any new vehicle or even just to fill every cigarette lighter in the vehicles we currently own.Update: Wrote this review May 18, 2019, and I'm writing this update June 1, 2021. They still work perfect, and one even survived a car wreck. Three years after buying the first two and two years after buying the third, still a great value.