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Knog Blinder Road 3 400



High performing, light, well constructed, and highly dependable – and bright enough for the darkest country lanes

At every product is thoroughly tested for as long as it takes to get a proper insight into how well it works. Our reviewers are experienced cyclists that we trust to be objective. While we strive to ensure that opinions expressed are backed up by facts, reviews are by their nature an informed opinion, not a definitive verdict. We don't intentionally try to break anything (except locks) but we do try to look for weak points in any design. The overall score is not just an average of the other scores: it reflects both a product's function and value – with value determined by how a product compares with items of similar spec, quality, and price.

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The Knog Blinder Road 3 400 is a relatively small (53 x 30 x 75mm) and low weight (105g) front light with, as the name suggests, a 400-lumen output. Its low bulk, light weight and yet powerful output make it perfect for commuting and shorter unlit lane rides.

Packed into a single, self-contained, fully waterproof aluminium head unit, the Blinder Road 3 400 features two 'LumiLed' white LED bulbs, one with a narrow beam and the other a wide beam. It offers 11 different modes – narrow, wide and dual bulb settings, all with options of low, medium or high, and two flashing modes should cover all your lighting needs. The only negative is a lack of side visibility due to the lamps being slightly sunk into the unit.

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Two buttons at the rear, above the top part of the clamp, control the light modes. The left hand button controls the lamp combinations and flashing mode, while the one on the right controls the brightness. Each button has a small light next to it, one (left) displaying battery life, the other (right) the brightness setting.

The light attaches to the bar with a silicone strap (two sizes are provided) which hinges via a metal clasp; this clicks and holds nicely in place with the help of a small top-mounted magnet. The bottom strap is replaceable, and a helmet mount is also provided.

The closure system performs well, holding firm on the bumpiest of roads, and the simple clasp means you can remove the light easily and quickly when leaving your bike or swapping it onto another. The pliable silicone strap also lets you adjust the angle of the light easily while on the move.

An integrated waterproof USB plug is nestled at the back of the unit, in between the straps, and is easy to flip out when charging is required.

Charging via a computer USB port can sometimes be tricky without using the short extension cable. Because the USB plug is located in between the straps, it has to be angled at its furthest open point so the straps don't get in the way; this then angles the whole light down so it won't slot into a laptop side port without raising the computer. It's only a slight inconvenience, really, and one I was happy to suffer in return for the light's low bulk and weight.

Full charging took 4.5 hours via laptop USB port. The charge indicator light next to the left hand function toggle button changes from red to green when fully charged, and vice versa as a warning while in use.

Knog Blinder Road 400 - beam shot.jpg

The Blinder 3 400 is more than capable of lighting up the darkest of country lanes, but the trade-off for the compact unit and low weight is shorter battery life. Run time on its highest, dual beam setting is only an hour and a half, but I did find that the dual beam on the medium setting, which lasts 2.5 hours, was sufficient for any unlit roads. Needless to say, if you need to be out riding in the dark on unlit roads for longer, this light isn't the one for you.

If you're riding on lit roads, using a single wide or narrow beam will significantly improve run times, and the eco flash mode will give you nine hours.

In use, the only real problem I had with the Blinder 400 was that the two toggle buttons are a bit 'form over function'. They're small and sit almost flush in the head unit, which is fine if you're wearing thin gloves, but in really thick, more bulky winter gloves they're hard to locate.

> Check out our guide to the best front lights and our beam comparison engine here

The Blinder 3 400 has been my main commuting light for the last four months, used five days a week for the 16-mile return trip that consists of 11 miles of unlit country lanes and 5 miles of city riding, with street lights to help. It's perfect for this type of trip, its wide range of modes coming to the fore. Its all-round performance has been brilliant and offers really good value for money. I'm more than happy to continue using it into British summer time and beyond!


High performing, light, well constructed, and highly dependable – and bright enough for the darkest country lanes

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Make and model: Knog Blinder Road 3 400

Size tested: n/a

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?

Knog says: "The Blinder ROAD 400 is the performance light for the ultimate road cyclist. Packing 400 lumens of light and using two of the latest high-intensity LUMILEDS LEDS ensures roads and paths are flooded with light, no matter where you ride.

"With incredible power:weight ratio and dual + constant flash modes, you won't find another light like this."

Tell us some more about the technical aspects of the light?

Light output: 400 lumens

Dimensions: 50 x 30 x 75mm

Weight: 105 g (our test model weighed 104g)

Light modes: 11 light modes: Narrow, wide and dual in high, medium and low and two flash modes.

Bike attachment: 2x interchangeable straps for handlebars 22-28mm / 29-35mm. Helmet mount included.

100% waterproof

Charges via Integrated USB

USB extension cord

Run times vary between 1.5 hours at it's most powerful setting to nearly 11 hours on its 'ECO flash' setting.

Rate the light for quality of construction:
Rate the light for design and ease of use. How simple was the light to use?

Easy to use apart from when wearing thick winter gloves as the buttons become hard to locate.

Rate the light for the design and usability of the clamping system/s

The closure system holds firm on the bumpiest of roads and allows you to remove the light easily and quickly when leaving your bike or swapping onto another. The pliable silicone strap allows you to easily adjust the angle of the light while on the move.

Rate the light for waterproofing. How did it stand up to the elements?
Rate the light for battery life. How long did it last? How long did it take to recharge?

Run time on its highest, dual beam, setting is only an hour and a half, but eco flash will give you nine hours.

Charge time via laptop USB port was 4.5 hours. Connecting the USB plug into a computer port without the USB extension cable can be annoying, especially when charging in a laptop.

Rate the light for performance:

I was really impressed by the all-round performance and durability of the Blinder Road 400 considering its relative light weight.

Rate the light for durability:

As above, I was impressed.

Rate the light for weight:
Rate the light for value:

Very good value for money if you intend to use it most winter nights, commuting and suchlike.

Tell us how the light performed overall when used for its designed purpose

Its all-round performance is brilliant.

Tell us what you particularly liked about the light

Its small size and light weight, considering its power lighting output. Faultless performance. The wide range of lighting modes. The ease with which you can remove it from the bike. I found it the perfect commuting and short distance winter training light.

Tell us what you particularly disliked about the light

The biggest negative is the size of the buttons and that they sit almost flush with the head unit, making them hard to locate when wearing thick winter gloves.

Connecting the USB plug in a computer port without the extension cable can be annoying, especially if using a laptop that might need something under it to provide enough clearance for the light.

Did you enjoy using the light? Yes

Would you consider buying the light? Yes

Would you recommend the light to a friend? Yes

Use this box to explain your score

Its all-round performance has been brilliant and offers really good value for money. It provides an impressive light output for its weight and small size.

The buttons could be slightly bigger, raised further from the head unit and spaced apart to help when using with thick winter gloves on.

Overall rating: 8/10

About the tester

Age: 40  Height: 5ft 7in  Weight:

I usually ride: Cervelo P3, Cervelo R3, Felt F1  My best bike is:

I've been riding for: Over 20 years  I ride: Most days  I would class myself as: Expert

I regularly do the following types of riding: road racing, time trialling, commuting, club rides, general fitness riding, mountain biking

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