The weatherproof, easily detachable LEDs are tiny enough to fit in your pocket and cute enough to not mess up the mojo of your purple Guerciotti’s vintage Cinelli drop bars. Their cheapness (about $17 each) has made them ubiquitous among the fixie-riding urban masses — Bike Snob calls them “Hipster Cysts.”

As much as I love my Knog Frogs, their short battery life annoys me. I was buying button cells at the local Radio Shack at a rate of four every three months to keep my pair alive and healthy.

They’re also quite dim. The streets here in San Francisco are well-lit after dark, so I primarily use my lights not to see, but to be seen, and for that, I want something as retina-scalding as possible. So, I upgraded to a pair 50-lumen Knog Boomer lights a few months ago, but the damn things gobble up AAA batteries faster than little Nibbler from Futurama.

So I was overjoyed to test the Australian company’s newest addition, its Boomer USB Rechargeable lights. They are the same size as the old model, except each light has a rechargeable Lithium Ion battery beneath the housing.

To charge up the light, you wiggle the weatherproof sealed plastic case out of its soft silicone sheath. A tail cap pops off, revealing a standard USB thumb. Plug that into any computer’s USB slot for a couple of hours and you’ve charged up the battery. When the indicator light turns from red to green, it’s filled, and you’ve got about 12 hours of flashing time before it needs another charge.

The LEDs are rated at 55 lumens for the white one in the front and 30 lumens for the red in the rear. They’re not quite as brilliant as the AAA versions, but they’ll keep you plenty safe in traffic. And the front LED lights up the road about 20 or 30 feet ahead of you at night — enough to be able to negotiate obstacles well before you’re on top of them.

Aside from a solid beam and a few different flash patterns, there’s also a “storage mode.” If you know you’re not going to be using the light for a few weeks, charge it all the way up, then hold down the power button for five seconds. This will burn the light until the battery is 50 percent discharged. After that, it’s safe for storage. Rechargeable batteries are fickle things, and they get confused easily. This puts the lights’ batteries to sleep comfortably.

One bummer on the Boomer: These lights are USB sticks, so why not include some storage capacity inside? I was actually shocked when I plugged the Boomer in and it didn’t mount on my Mac’s desktop. As such, this is probably the only USB device I carry around that isn’t loaded with a few Black Sabbath or Pink Floyd bootlegs on MP3.

WIRED You can stop chucking batteries. Sealed plastic case keeps the wet out. Rubber loop-and-hook design is easy to get on and off. Front and back are different shapes so you won’t mount them the wrong way. One charge lasts for about 12 hours flashing, three hours in steady light mode. They come in several colors, including hot pink (of course).

TIRED Light is too bulky to slot between two USB cables, so you need to use the last port in your stack. I’ve seen better battery life from rechargeables. If I could carry files on here, I would — hey Knog, how about adding a little flash memory next time?

Photo by Jon Snyder/Wired