Boulder Pack Co. Compact True-Capacity 20000 mAh Power Bank (with 2 Fast-Charge Smart-Output 3.0A Ports, Pass-Through Charging & TSA Compliant) Compatible with iPhone, iPad, and Android

As a power bank, this is reasonably priced for the capacity so it is an ok purchase.However I bought it for the passthrough feature (charge while powering output ports), and that is not quite satisfactory: first, the output voltage while charging is about 4.6v (versus 5.1v when not charging), which affects the current that devices are able to drain; second, when disconnecting the charger there is a 35ms glitch in the output (see scope picture) during which voltage goes down below 4v. This may cause devices to reset.

Update: Been in heavy use for 6 months, passthrough charging my dashcam and running it parked just about every day, all day. Noted a slight curvature/bulging of the outer case after the past month or two, when day temperatures have been consistently high while my car sits outside. That said, the bulge hasn't grown and the battery has lost only a little usable life. Figuring I'd play it safe (lithium ion batteries in a hot car and all), I shot seller Hillstone a message inquiring about warranty details. I hadn't even checked my Amazon messages for a reply by the time a fresh replacement was at my doorstep! All my comments from the original review still hold true. Grateful for a solid product and a solid seller.As another reviewer here, I (cautiously) use power banks to run a dashcam while parked. Formerly I ran two (!) 20000mAh power banks daisy-chained to make it through a full day/night (not efficient, I know). This one easily replaced them, and runs even longer. If anything it's probably evidence that my old power banks didn't really have their advertised capacity, but I'm super happy with the run-time on this device. Also didn't notice it getting hot at all using passthrough charging (while I'm driving and still have the dashcam on). Another point I'd like to make is how well made the connectors are. With my old power banks, cables would constantly get disconnected, but in this one they sit super tight. Charges in a jiffy too.

Compared to other batteries, it is compact and light. It is perfect for roadtrips to charge the phone and the camera. Allows to charge 2 devices at the same time via USB.The full battery allowed me to charge my iPhone 9 times and it took roughly 1h30mins.Charge 1 from 10 to 100Charge 2 from 8 to 100Charge 3 from 9 to 100Charge 4 from 12 to 100Charge 5 from 6 to 100Charge 6 from 11 to 100Charge 7 from 10 to 100Charge 8 from 1 to 100Charge 9 from 9 to 28To charge the battery from 0 to full again it took around 6hr30mins.

Very disappointed. While it will charge Android, it does not do turbo charging. The "no questions asked" return policy is not accurate as it asks why you are returning the product before you get the shipping label. Return shipping is taken out of refund.

It REALLY is 20,000 mAh!!! Other power banks say they are 20000 mAh but they are not. I own two others ( including another 20,000 mAh one ) and they do not last as long as they should. The conversion process fro 3.7 volts to 5 volts actually takes away about 1/4 of the mAh. So you may have 20,000 mAh inside, your really only getting about 15,000 mAh. The product is a bit on the heavy side but that's because your getting the real deal! Product has a strong outer case as well Not the cheap plastic you get with other power banks.

Got this power bank so I could use Parking Mode on my Vantrue N2 Pro. I've used it for about a week. Works well. I live in a city and even on a city street this could support probably 2 full nights of motion-detection-based recordings. Only had it for a week, can't speak to durability or how long it lasts, but seems generally well built. Pass-through charging capability is good for dash cam so I don't have to keep switching what's plugged in. I just keep the cam plugged into the power bank and plug the power bank into car outlet; it powers the cam AND charges the power bank.

Purchased on June 12th and used it often. I keep it in my backpack that goes with me to my office job and I use it when not around a charger. It would charge my iPhone 8 Plus from 20% to full in less than 20 minutes and do it 5-6 times before needing charged. Problem is it just quit working. It charges to full just fine, all 4 LED’s are on, but it will no longer charge a phone. I’ve tried different charging cables and different devices and nothing happens. I’ve contacted the company and am waiting to hear back.

I've been looking for a pass-thru power bank with a large capacity and this one does the job. The only reason why I knocked it down the star, even though it does everything as advertised and very well, is that one of the 4 LEDs on the device appears to be broken. It doesn't affect the battery itself, but I can only see whether it's full or half charge or less now because the one just below the top is out. Still a good product that does what it says, but more quality control might be needed.