This ultra-thin power bank is my new favorite traveling accessory – and it's affordable

For hikers and runners, every ounce you’re carrying counts. Power banks can be a big challenge because you need something powerful enough to charge your devices, but still lightweight and compact enough to take with you. 

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This is where the Nitecore NB Air comes into play—a power bank the company describes as a “waterproof, competition-grade energy bar.” Nitecore is known for its innovative power banks, such as the NB10000, which combines thin batteries, a polymer chassis, and carbon fiber to create a lightweight solution for those on the move. But the NB Air takes the concept of thin and light to an entirely new level. 

The NB Air is a 5,000mAh/19.4Wh power bank featuring a single 18W input/output USB-C port that supports two-way Power Delivery (PD) and Quick Charge (QC) 3.0. All of this is packed into a sleek bar measuring 4.4 x 1.9 x 0.38 inches (112 x 48 x 9.7 mm) and weighing just 3.14 oz (89 g), resulting in an impressive energy density of 310 mWh/g.

This remarkable efficiency is achieved through a lightweight composite frame and carbon fiber shell that weighs only 0.49 oz (13.8 g). Despite its lightweight design, the exterior is robust, built to withstand torsion, and is rated IPX7 for dust and water resistance — fully dustproof and capable of withstanding immersion in water up to one meter for 30 minutes. The rounded corners of the shell are specifically designed to absorb impact forces and prevent damage to the fabric of coats or rucksacks. 

On one end, you’ll find a USB-C port, a four-LED power level indicator, and a capacitive button to illuminate the power level indicator. The power bank is engineered to perform in a wide range of environments, operating effectively between 14°F and 95°F (-10°C to 35°C).

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To ensure the safety of the battery, the unit is equipped with essential safety features, including overcurrent protection, short-circuit detection, over-discharge protection, overcharge protection, and overvoltage protection.

The only downside to this package is that it doesn’t come with a USB-C cable or pouch to hold the power bank. This is a small complaint, but it doesn’t stop it from being an amazing package. 

ZDNET’s buying advice

If you want a power bank for when fractions of ounces matter — but still want it to be tough — the Nitecore NB Air is hard to beat. Not only is it thin and light, but it’s also built to withstand outdoor conditions, offering high levels of dust and water protection.