This is one of the most convenient tech accessories I’ve ever used

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AmazonI make a habit of recommending external batteries a lot, and for good reason.

Rechargeable electronics are extremely convenient, but when they're dead you can't just pop in a fresh set of AAs.

I typically recommend a relatively inexpensive battery, but if you're in the market for a simple product that solves a basic charging problem, I recommend Fluxmob's BOLT. 

I've written about this product before, but I just started testing it again recently. And it continues to be one of the most clever gadgets I've used. On the one hand, it's a tiny, 3,000mAh external battery pack with a USB port for device charging. On the other, it's a power adapter that plugs into your wall, which can charge its internal battery and that same device simultaneously.

Its power-adapter shape also means you can connect this battery pack directly into a wall, instead of using a third-party adapter and an additional cable.

That combo makes the Fluxmob's BOLT unmatched in terms of convenience. Some USB battery packs don't let you charge devices while they charge. Others do, but they're shaped like, well, battery packs. The Fluxmob BOLT looks more like half of a standard MacBook charger (albeit it in more funky colors), and won't look out of place when it's plugged into an outlet.

My favorite design touch with this product is the grid of four LED lights on its front. They light up when the Fluxmob BOLT is charging to let you know how full its battery is up to that point. It's a pretty common feature on external batteries, but Fluxmob's LED's are always on while it's charging (other batteries require you to push a button), so it's easy to know when to unplug and pack it. 

In terms of sheer convenience, the Fluxmob BOLT has earned my recommendation. It's a hybrid product that doesn't compromise its roles as a battery or charger.

If you've put off buying a portable charging pack because of bulk and perceived lack of use, I strongly suggest you give this one a look.

Fluxmob BOLT, $44.95, available at Amazon