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With 24 hours of illumination, a handy battery indicator and its auto eco mode, Kryptonite's street-focused front light is host to some thoughtful safety additions. While set-up is on the fiddly side, if you're a commuter with a bit of bar to play with, you'll likely find a snug and ongoing home for the Street F-300.
The US folk who've been making locks for four decades have set out to illuminate rush hour streets with their China-produced Street Light series. Ranging from 150 to 800 lumen, these USB-rechargeable LED lights are intended to help you see and be seen on the tarmac.
At 11.5cm in length and 4.5cm wide, the F-300 (F for front light, 300 for lumens) is not as compact as some front lights out there, nor is it the most lightweight at 139g, but it still boasts a neat torch-style lamp with some interesting safety features.
While its six modes provide enough choice for daylight, dusk and darker conditions, they're simple enough to get to grips with quickly. They comprise a high (300 lumens), medium (150) and low (60) steady beam, plus a daytime and night-time pulse (300 and 170) and an economical flash (60).
On test, the F-300's low beam provides enough visibility to ensure I feel seen at night without dazzling oncomers, while its pulses are more pleasant and predictable than some of the more erratic flashing options out there. There's also a memory feature – meaning it switches back on to the mode you left it in. So far, so simple.
Kryptonite says 'this light is great for lighting the way, for most city commuting scenarios', and it's about right. The F-300's output doesn't turn night to day, but it does cast a decent beam on the road ahead. And the light's beam width supports the commuting claim too – its illumination is broad enough to light up road signs (notably wider, in fact, than another 300 I tested, Infini's Tron, full review to come). But what Kryptonite's front light gains in width, it pays for in pinpoint brightness – without street lights, you'd need more power to see the bumps in the road.
To bolster this light's being-seen cred, Kryptonite has added a lateral illumination feature – little light ports to provide more peripheral visibility to surrounding traffic. Handy, it says, for riding across lanes. The windows are small, so output is not terrific, but it's a thoughtful safety feature nonetheless.
Mounting the light, says Kryptonite, is easy. However, the ability to find an appropriate home on your bike for this lamp might just be its main drawback. The bracket-and-ratchet-strap system is simple enough in theory: remove the unit from the bracket using the quick-release button, wrap the bracket round your handlebar, feed the strap through the bracket until you get a tight fit and finally, flip the bracket lever to secure it.
How easy it is in practice depends on your setup – specifically bar width, cable routing and whether you've got electronic gearing or not (because if there's no Di2 junction box, you could secure the light to the head tube). With my setup, the F-300's mount system proved a little too cumbersome to allow for a neat attachment. Eventually, and after some frustrated fiddling, I got there. Once on, it provides a tighter and more secure fitting than many rubber-banded options.
A better performance comes from its hassle-free mounting port. The ease with which you can attach and unattach this light from its dock makes grabbing it and running for the train far easier than is often the case. Especially when compared with the rubber attachments that require nimble fingers – tricky on cold commutes.
Battery life is a bonus. A key advantage to Kryptonite's F-300 versus some others out there is its ability to keep you rolling safely for longer between charges, promising up to 24 hours on its lowest 60-lumen setting (Infini's Tron lasts just 8hrs max, pulse or constant). By contrast, though, the full 300 setting only lasts for its claimed 90 minutes (Tron's lasts 2hrs). On test, this was bang on, settling on its longer-lasting 60-lumen 'get you home' flash mode after exactly that.
Kryptonite has built in a battery indicator which glows green, yellow or red through a transparent power button, to provide a warning that the lamp has a respective 100, 50 and 25% battery life remaining. When you hit 10% battery, the F-300 automatically switches itself to the economical flash mode in a mission to get you home safely. When you need to recharge, the port allows simple access for a Micro-USB cable – and its lithium battery reaches green, or over 50% full, in under two hours.
The F-300's waterproof capability is excellent, with no signs of water damage after many soggy commutes – and with a two-year warranty, it seems Kryptonite has faith in that too.
At £35.99 it's on a par with other 300s, the Infini Tron and Saturn (full reviews to come), and looks to kick out a bit more light than some higher-number options such as the Blackburn's DayBlazer 400, which is £3 cheaper.
A sturdy day-to-night light with decent beam width, added safety features and a pocket-pleasing price tag
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road.cc test report
Make and model: Kryptonite Street F-300
Size tested: 300 lumens
Tell us what the light 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?
It's aimed at commuting on the road. Kryptonite says 'this light is great for lighting the way, for most city commuting scenarios'. The description is accurate for its intended use and performance.
Tell us some more about the technical aspects of the light?
SPECIFICATIONS & FEATURES
Modes include HIGH STEADY, MEDIUM STEADY, LOW STEADY, DAYTIME PULSE, NIGHTTIME PULSE and ECONOMIC FLASH
FULLY USB RECHARGEABLE - No batteries to buy or replace
Run time up to 24 HOURS
Side illumination ports allow cyclist to be seen when riding across traffic lanes
Memory Function-Light turns on at the last mode it was turned off
Power saving function- 10% power or less, lights will automatically switch to lowest lumen output
Built in battery indicator- Red illumination = lower than 25%, Yellow = 50% - 25%, Green = fully charged
Mode Run Time (Hrs) Lumens
High Steady 1:30 300
Medium Steady 3 150
Low Steady 11 60
DayTime Pulse 8 300
NightTime Pulse 10 60/170
Economic Flash 24 60
It's not the smallest or lightest, but it still boasts a neat torch-style lamp encased in a smooth, durable and waterproof outer. The easy-on-easy-off is a particular treat, though the handlebar clamp lets it down a bit.
The six-mode design had everything I could need from day to night without mode overload. The memory function was an easy way to get going each time I got on my bike, and the button itself is not in the least bit fiddly – and even comes with battery indicator colours. The lateral movement is a nice addition too, though the generous beam width meant I didn't need to use it.
Dreamy on-off mounting port, but the bracket itself could be neater and an overall more pleasant experience to fix to your bike. It's quite cumbersome, leaving few options for positioning.
No problems whatsoever, the light performed without exception in all-weather commutes.
Battery life lives up to reports, 90mins on full and 24hrs on flash – with the bonus that it flicks onto eco mode at 10%, again tested and as advertised.
Beam width was good, though I felt the pinpoint brightness suffered to this end.
After one month of riding in all weather, there were no signs of this light slowing down. So far, so good.
There are lighter 300s, but it's definitely not the heaviest either. For its performance, it's about right.
For £35.99 it packs a punch for your commute without hurting your pocket too much. I have spent this much on lights that have conked out sooner – it's a good price for a light that's a good all-rounder.
Tell us how the light performed overall when used for its designed purpose
For commuting under streetlights, the light performs very well. You're visible, and you can see road signs and the road ahead. However, it's not hugely pinpoint bright, so on dark sections more brightness is needed. It copes well with the rain, and provides added safety features – so it's a good all-rounder.
Tell us what you particularly liked about the light
The power save that kicks in when you're under 10%, and the super-easy on-off mounting port for the lamp.
Tell us what you particularly disliked about the light
The chunky bracket, which just didn't fit to my bike neatly.
How does the price compare to that of similar products in the market, including ones recently tested on road.cc?
It's on a par with other 300s, and similar to some higher-lumen options (which don't necessarily produce as bright a beam).
Did you enjoy using the light? Yes, very much so, once it was on my bike.
Would you consider buying the light? No, I need a brighter option as inevitably my commute will have a dark section.
Would you recommend the light to a friend? Yes, depending on their setup and commuting needs.
Use this box to explain your overall score
For the price point, this light is about bang on. It feels robust, and has some really handy features, from the battery indicator to the low battery flash mode. It loses some points for the chunky handlebar clamp, but quickly gains them back for the on-off mounting port. Once the clamp's on your bike, the light can easily be taken on and off in seconds.
About the tester
I usually ride: My Scott Foil My best bike is: Oldie but the goldie, CAAD 8
I've been riding for: Under 5 years I ride: Every day I would class myself as: Novice
I regularly do the following types of riding: road racing, cyclo-cross, commuting, touring, general fitness riding, triathlon, audax