My Brooklyn apartment isn't exactly what you'd call emergency-proof, though I picked up a number of tools before and after Hurricane Sandy that make me feel a bit more at ease during storm season. But it wasn't until Eton's Blackout Buddy H20 landed on my desk that I realized I don't even have a reliable source of light in case the power goes out. Sure, I have a pretty standard-issue flashlight, but I couldn't tell you what kind of batteries it takes or whether it's even working right now. That's what makes the $9.99 Blackout Buddy so appealing. It's a tiny, water-activated emergency light that's a much safer alternative to candles or matches. It provides three days' worth of light and can be stored for up to 10 years, making it an excellent addition to your emergency preparedness kit.

Design and Performance

The Blackout Buddy H20 is a tiny plastic device, about the same size as a Zippo lighter. It measures 2.6 by 1.3 by 0.6 inches (HWD) and weighs less than an ounce, making it tiny enough to store just about anywhere. And you won't need to worry about checking on it once you've added it to your emergency kit, as the Blackout Buddy comes housed in environment-proof packaging designed to protect it from degradation for up to 10 years.

The top of the Blackout Buddy is home to three small LEDs which are protected by a removable plastic cap. The bottom features an ovular cutout that exposes what looks like four metal sheets sandwiched by cardboard.

To activate the Blackout Buddy, all you have to do is dip the open bottom end in a small cup of water. This will activate the battery module, and the LED lights will instantly power on. The Blackout Buddy's magnesium oxide battery module is free of cadmium, lead, hexavalent chromium, and mercury, so it's totally safe for the environment.

To stay fully illuminated, you just have to add water once a day. Eton claims the Blackout Buddy can last for up to 72 hours; I found it worked closer to 120 hours, although the brightness of the lights diminished significantly after those first 72 hours. Before then, the brightness of the Blackout Buddy was comparable with the LED flashlight on my iPhone 5s. The Blackout Buddy casts a bluer-looking light that's more concentrated in the middle, but did an equally good job of illuminating a 10-foot swath of a completely dark test room in the PC Labs. It provides more light than a candle, and you don't need to worry about a flame.

I found that I didn't need to add water to the Blackout Buddy on a daily basis as recommended. After giving it one good dip on day one, it remained fully illuminated for the rest of its battery life. But while water activation is safe and convenient, the downside is that there's no way to turn the light off once you've activated the battery, so the Blackout Buddy H20 is really only good for one use. Then again, hopefully you won't have to use it at all.

Conclusions
Many of us now carry around phones that do double-duty as flashlights, but you don't want to worry about battery life in an emergency. The Eton Blackout Buddy H20 provides plenty of light for at least three days, and it's cheap enough that you won't feel guilty buying one, even if you're already pretty sure that your flashlight contains working batteries. That makes it a great addition to your purse, glove compartment, and of course, your home emergency kit. I already plan on adding one to mine.

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