It's a universal law: Phones always conk out at the most inconvenient time. Preempt the problem! Keep a portable power bank on hand and you'll always have a way to juice up, even if you're not near an outlet. Thankfully, the most popular one at Amazon just dropped to an (heh) electrifying low price. The No. 1 bestselling Loveledi portable power bank bundle is steeply discounted right now for Memorial Day. You'll get two of them — we repeat, two power banks — for $20, both with 15,000m Ah batteries. Just $10 a pop!

Amazon

Loveledi Portable Charger Power Bank, 2-Pack

$20$30Save $10

Universally compatible, these speedy power banks will charge your phones, tablets and more.

$20 at Amazon

Each of these Loveledi power banks pack a lot of charge into a half-inch-thin frame. The battery provides about four or five full charges for your iPhone. (The Pro series of certain iPhones have larger batteries and may get only three charges from one of these power banks.) Considering there are two chargers in this pack — and how small they are — you could carry over a week's worth of charges in a single pocket!

"Amazing battery life," confirms a shopper. "I have used it several times over the past week with only one full charge. I haven’t charged it yet with life in it still! I got the 2-pack deal and gave one to my mother as a gift...."

That portability is one of the major selling points. "I can’t be stuck at a charging station. I need to move around a lot. This has changed my life!" said one restless reviewer.

Another satisfied shopper added, "This power bank works great. It's lightweight and portable, thus can be taken anywhere. The charging speed is what really impressed me. I have several more expensive power banks but this one is just as powerful as those"

These power banks include a sensor that automatically detects the voltage and amp requirements of a connected device. That means you never have to worry about damaging your phone by overcharging.

Did we mention these are also airline-safe? Toss in your carry-on bag and they'll keep your phone charged no matter how many movies you want to watch while you're in the air. "Bought these when I was traveling on a plane for 15 hours. Charged my AirPods, phone and watch on one for almost two days," said one traveler.

Seriously, these are a great value. A single Loveledi power bank currently goes for $15, so getting two for $20 is just ridiculous.

Amazon

Loveledi Portable Charger Power Bank, 2-Pack

$20$30Save $10

Fast charge two devices at the same time with these super-useful power banks.

$20 at Amazon

The reviews quoted above reflect the most recent versions at the time of publication.

If you have Amazon Prime, you’ll get free shipping, of course. Not yet a member? No problem. You can sign up for your free 30-day trial here. (And by the way, those without Prime still get free shipping on orders of $25 or more.)

Here’s everything you need to know about Memorial Day sales, plus all the best deals on the internet — kept fresh by our team of shopping editors. See all of our Memorial Day sales coverage across Yahoo, Engadget and In the Know, here.

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