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The Knog Plus Twinpack lights are impressively bright, weigh the same as a bag of crisps and clip/unclip in seconds. Some lower than claimed burn-times and slightly iffy finishing are the only potential issues, though they could be just a little cheaper too.
To be clear, the burn-time issue was limited to one mode, but as that was 'steadily-on', I found it an issue. I prefer a constant light on the front – to assuage those drivers who claim flashing lights makes it hard to judge distance, and to avoid giving myself some kind of strobe-induced fit. Knog claims 2hrs solid light, but this 40-lumen white COB (Chip On Board) light only managed around 1hr 45mins before dying. The low battery light comes on at 1 hour.
Fortunately there's a workaround. While the fast Strobe is claimed to last 8.5hrs it's very distracting, as is the arrhythmic Fancy Flash (10hrs). Luckily, Pulse – which fades up and down smoothly from full power – gives at least the claimed 4.5hrs without running dry, and is noticeable without being distracting.
The final mode is Eco Flash, which allegedly gets a whopping 40hrs from one charge. As it's off more than it's on I never felt like relying on it. Front and rear offer the same options, with a quick press of the button cycling modes and a long press for on/off. A useful red indicator warns of low battery levels.
While the rear light has half the output at 20 lumens, it's still impressively bright, even in daytime. On overcast days, it bounces noticeable light off frames and even dry, unshiny tyres if you peer back to check it. I used them routinely to be seen in the day, and found them highly visible whatever the weather.
The fittings are great. The selection of silicone bands makes finding a suitable size easy, and the tiny brackets fit in seconds. The lamps then slide in and secure by magnet. It feels precarious at first, but I still have both lights (rear mounted vertically, front horizontally) despite routinely spanking them over truly broken Welsh winter roads at considerable speed. Their tiny mass – they're 12g each – means it would take a severe shock to accelerate them beyond the magnet's force.
The main bodies are also hooked like pen caps to slip over pockets or straps, and made of slightly flexy rather than brittle plastic that can take the odd knock. The air pockets in whatever fixes the lens to the body don't look good, but I've had no leaks or breakages yet, despite plenty of vibration and biblical rains.
The USB contacts are covered when the lights are in the mount, but not sealed, so the rear in particular can get dirty. A wipe with a finger is enough to clean the thin metal foil – plugging them in to charge without doing so (they're a male fitting, so no cable) will lead to rapid wear.
These Knogs charge from empty in around 4 hours (in a phone charger plug), and a bright light makes it clear when they're full. And really, that's the Knog Plus Twinpack all over: they're quick, easy and effective, plus they really are light – in every way.
There's no shortage of 'be seen' bike lights, but few are this small and light. Electron's Pod USBs are great, for instance, but twice the weight and £13 more at £45. They do burn a little longer, however. Even Guee's dinky, simple COB-X lights weigh twice as much, and are £35.
Go much lower on price and output/clamp design tends to suffer, though there are exceptions. Lifeline's USB LED set stands out from a sea of similar designs with good burn-times, great build and a wispy 35g weight. The few features they have barely work, but you might not care at £20.
Bright, exceptionally light and super-simple to use, these tiny USB lamps are limited only by burn-times
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road.cc test report
Make and model: Knog Plus Twinpack
Size tested: Dimensions: 14 x 66 x 18mm
Tell us what the light set is for and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
Knog says these are "super-bright, 100% waterproof and totally versatile USB rechargeable bicycle lights. Mount the lights to your handlebars, forks, steaposts and stays, or use the integrated wearable clip to attach the light to your shirt pocket or panniers."
They are indeed bright and versatile, and very easy to use.
Tell us some more about the technical aspects of the light set?
The front light is 40 lumens, while the rear is 20. They weigh 12g each (without the mount), with claimed burn times between 2hrs and 40hrs, and a charge time of 4hrs.
Also, Knog list these features:
-Efficient Chip on Board (COB) LEDs designed to provide maximum brightness level for up to 90% of the battery burn time for each mode.
-100% WATERPROOF : The Plus (+) is IP67 tested and 100% waterproof against all elements
The clear panels look cheaply glued on, but otherwise they feel solid.
Silicone straps, a magnetic clamp, pocket-clip shaping and USB recharging mean these couldn't be easier to use.
Silicone straps are simplicity itself. Magnetic attachment to clamp is impressively secure.
Withstood hours of torrential rain without issue.
The front light died in well under the claimed 2hrs (low charge light comes on in 1hr) when used on steady mode. The rear can go 4-5hrs without failing in flashing mode. Both charge up in just a few hours, and an obvious light makes it clear when they're full.
They're both impressively bright for such tiny, lightweight lamps, but you have to put up with a flashing front light if you're riding longer than 1hr 45mins.
The USB connection of the rear light is vulnerable to dirt and water, though a quick wipe before plugging in removes problems.
At 37g for the pair, they're unnoticeable.
Excellent - assuming you're either happy with a pulsing/flashing front light or don't plan to ride beyond 90mins.
Tell us how the lights performed overall when used for their designed purpose
Give a strong and simple boost to visibility even in daylight.
Tell us what you particularly liked about the lights
Light, bright and very easy to use.
Tell us what you particularly disliked about the lights
Short burn time of the front light - and no steady-shining reduced-power mode.
How does the price compare to that of similar products in the market, including ones recently tested on road.cc?
There are cheaper options, but the majority of sets are considerably more expensive.
Did you enjoy using the lights? Yes
Would you consider buying the lights? Yes
Would you recommend the lights to a friend? Yes
Use this box to explain your overall score
If the front light could handle 3-4hrs on steady, these would be a 9. It copes on Pulse, which is OK, but not as good... so 8 it is.
About the tester
I usually ride: GT GTR Series 3 My best bike is:
I've been riding for: 10-20 years I ride: A few times a week I would class myself as: Experienced
I regularly do the following types of riding: general fitness riding, mountain biking