This is one of the best value power banks I've ever tested, and it's 20% off

ZDNET's key takeaways

It's not often you can pick up a top-tier 20,000mAh power bank for $30. Well, you get that here, and the current 30% coupon makes this an even better deal. It has a helpful display for charging specs.

I'm a big believer in buying quality gadgets and accessories, because I've been bitten by the "buy cheap, buy twice" curse more than once. Quality doesn't always have to break the bank. In fact, you can sometimes find something that's unbelievably good for a great price.

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One such example that offers fantastic value for money is the Cuktech 20,000mAh power bank. If you're looking for a cheap and cheerful power bank that delivers, this Cuktech unit has you covered. I've been using it to power my smartphones, tablets, and even smaller laptops.

Cuktech 20,000mAh power bank tech specs

The bottom line is that this 20,000mAh power bank is a good one, built to a decent spec. The 20,000mAh capacity is actually 20,000mAh, which is reassuring given how many budget power banks I test that try to fool buyers by passing off lower capacities.

The power outputs are also as specified, with the power bank capable of 45W output using a single USB-C port. It can be recharged at 40W, which means it can go from flat to 40% in about an hour using a 40W+ charger.

Also: I tested a 9,000,000mAh battery pack from eBay - here's my buying advice

The built-in cable is also durable and looks like it will last the life of the power bank. The LCD offers an at-a-glance view of the charge capacity, much better than a few tiny LEDs that some power banks still use.

Everything is encased in a tough, durable plastic shell, with a grip pattern on the underside. I've been testing this power bank for a few weeks, throwing it into a bag or rucksack, and I can tell you now, this one doesn't expect to be mollycoddled!

As far as safety is concerned, I've pushed this power bank hard under a variety of loads, and not had a problem with heat or the power output being throttled. I've even had it charging devices while in a bag -- quite the heat test for a lot of power banks -- and this one didn't have any problems. 

ZDNET's buying advice

The Cuktech 20,000mAh power bank is a fantastic power bank, and it comes at a great price. I don't look at the retail prices of things before reviewing them, and honestly, I expected this one to be around $60. 

It's not. Normally retailing for $30, this one represents excellent value for money, but currently there's a 30% coupon on Amazon, bringing the price down to an unbeatable $21.

This Cuktech unit is perfect for those with smartphones, tablets, and even smaller laptops. You could spend two or three times as much to get a power bank with a similar spec, but you would not get anything extra.