BONAIPortable Charger 20000mAh Power Bank 4 USB Output & Dual Input, Aluminum Polymer External Battery Pack for Road Trip Camping Compatible with iPhone iPad Smartphone Tablet etc. -Rose Gold

The product i'm reviewing is for the white 20000 mAh Power Bank.It came in a simple box with two 1' male USB-A to male micro USB-B cables, a manual, and some other product/customer service papers. The battery pack itself weighs in at about 14 oz. On first inspection, it is well designed with no observable or palpable weakness in the case. There are two female USB-A ports located at the top of the pack for charging your phone with the two ports separated by the flashlight. On the upper left side, there are two female micro USB-B ports for charging the battery pack itself. The flashlight button is slightly recessed from the case preventing accidental activation and button presses were firm and clicky, providing a nice tactile response. Operating the flashlight was also very simple; two quick presses to turn on or off the light, useful in case of any accidental presses so that it won't drain the battery life in your pocket or bag. The picture attached shows the product's dimensions, but here they are: 6.75" x 3.5" x 3/4".For easier personal use,I got some rubber bands and banded the two micro USB cables together, as seen in the attached photos. That way I won't lose them as easily and they'll be a dedicated charger for the powerbank. The cable build quality seems to be of average build, with adequate strain relief on each side. Personally, I wish it came with a custom cable with a single wire that had two heads, but including two separate cables allows versatility, allowing the charging cables to be used to also charge a phone/phones and not just the powerbank. The flashlight has a narrow beam pattern compared to my phones light/flash, but it is bright enough for emergency purposes. If you don't wish to use the light on the battery pack, you could always charge your phone and use the phone's flash as your light source, but it's always good to have a fallback just in case.To test the product, I first fully charged it until the 4 LEDs no stopped blinking, indicating a full charge. I then used it as my primary charger for my Samsung Galaxy s8 until the powerbank provided no more power. I have been using the app, AccuBattery, to keep of the charging history, charging time, and discharge history. Based on the estimates of AccuBattery, the battery of the s8 is designed to be 3000 mAh, but the estimated battery health and estimated capacity are now at 95% and 2853 mAh respectively. To preserve the battery of the phone, I generally never let it run empty and I only charge it to 80% to keep the non-replaceable battery wear to a minimum. Charging the battery to 80% usually provides me a charge for ~24-27 hours until it hits 20%, so I charge once a day. The powerbank provides enough power to fast charge my phone, reaching the 80% mark within an hour of initiating a charge.Presented below are the charge percentages of the phone over the course of a week.1. 23% → 80% = 57%2. 20% → 80% = 60%3. 26% → 80% = 54%4. 07% → 80% = 73%5. 21% → 80% = 59%6. 21% → 82% = 61%7. 11% → 73% = 62%Total % charge = 426%This roughly equates to charging the phone 4.26x if the charge were to be from 0%. This is a little less than what the manufacturer estimates at 4.5x but then again, the charger has the capacity to power a single phone for more than a week.To complete testing, I decided to charge it on my Ravpower 6 port charger, using the two cable charging method. Having the stopwatch on my computer on until the LEDs stopped blinking, it took about 5 hours and 20 minutes.Overall, the product does as it is designed and I was able to fast charge my phone for a week using solely the powerbank. It should work great for long travels for a single phone or short trips for multiple devices without access to a plug.

I love Bonai! I travel frequently and love to use my smartphone as my primary camera. However, battery life was always a major constraint, as generally my phone would be dead by mid-afternoon and I'd miss out on great photography opportunities for the balance of the day and evening. So earlier this year, I purchased a Bonai10,000 mAh power bank, and it has been an awesome addition! Using my smartphone camera non-stop, I never came close to running out of power. And it was compact (easily fit in my pants pocket), lightweight, and perfect for travel. And so this week I purchased the 20,000 mAh version so that I'd have enough juice for multiple devices. The new power bank charged perfectly and can provide multiple charges for up to four USB-powered devices simultaneously. It is attractive in its sturdy silver casing, still compact and lightweight (maybe an inch larger than the 10,000 mAh model), and the indicator lights allow for immediate status on charging and remaining capacity. I was a bit reluctant to buy devices like these over the internet due to concerns about the quality of the product I would receive, but I am completely sold on Bonai. Their products are reliable, useful, and durable. I couldn't be more satisfied or pleased. Bonai has added a ton of value to my travel experiences. I will never miss a great photo opportunity again! And the price-value is tremendous -- this is a bargain purchase.

So, to try and sum everything up. My wife has this bonai charger I got about a year ago. It impressed me so much, I bought a usb backpack so I can have my own charger. I did what it said and used a 5v charger, or get an iPad charger, same same. It took about 6-8 hours to fully charge. You can use a micro usb or lightning cable if you have 12-14 hours to spare charging, and that’s from experience. I made a list to make it easier.ProsCharges fast with the right adapter (5v2a)Charge lasts foreverI’m on charge 3 for iPhone and it’s on 4 dotsIt’s got 4 slots for charging stuffIt will charge a tablet or phone quickIt’s not expensive for the qualityMust I go onConsToo heavy for weaklings, lolCan’t manhandle input charging connectionsEverything is labeled to clearlyToo much pride and quality put in productCaptain Obvious says, get this product or other bonai products, cause that’s what I’m gonna do to support this company. I can’t really say anything bad about it. I have to make up Cons. If you got unlucky and got a glitched product from an assembly line (duh, it happens), get another one and move on.