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Blackburn's Mars 4.0 rear light is a clever little light that comes with 3 different mounting options.
We really liked it when we reviewed its previous incarnation 4 years ago; though it's changed a bit since then, it's only got better.
It still has the amber side leds, but the 5 red LEDs on the Mars 3.0 have been upgraded and turned into one superbright 1 Watt LED, creating even more rear illumination. Whereas the model we reviewed then needed a screwdriver to undo the 3 screws that held the batteries in, the 4.0 unclips with a coin to change the 2 AAA batteries.
Not that you'll have to do that often, at 50 hrs runtime on full and a whopping 150 hrs on flashing.
As always with Blackburn stuff, the rear light is really well made, and the casing has stood up to the usual abuse and the wet weather we've been having over the winter. As with all their lights, this one too is covered with a lifetime warranty.
Apart from the overall goodness of this light, I was particularly impressed that it comes with a dedicated rack mounting bracket; something I usually have to DIY with other lights. It also comes with a tool-less seat post mount, and the light case itself has a belt clip which is what you clip into the bracket(s).
At 76 grams, it's not going to affect performance too much, and it will definitely get you seen in all but the brightest sunny weather.
Deserves consideration, especially as it can be had half price online at the moment.
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Make and model: Blackburn Mars 4.0 rear light
Size tested: n/a
Tell us some more about the technical aspects of the product?
* Blackburn's most powerful rear flasher
* 1 Watt ultra-bright red LED
* 2 Amber side LEDs for side visibility
* 50hr steady, 150hr flashing runtimes
* No tool battery installation
* 2 AAA batteries included
* 3 mounting options included: belt clip, seatpost clamp and reflector/rear rack mount
The quality you've come to expect from Blackburn.
It really is quite bright for such a small light. The amber side lights help a lot, too.
These lights have a reputation for lasting a long time.
76 grams, including batteries and seatpost mount. That's not a lot.
Once the mounting is in place, it's a doddle to use.
Even at RRP it's value for money, let alone at half price currently available from Ribble.
Tell us how the product performed overall when used for its designed purpose
It worked really well.
Tell us what you particularly liked about the product
It comes with a rack mount.
Tell us what you particularly disliked about the product
Did you enjoy using the product? Yes.
Would you consider buying the product? Yes.
Would you recommend the product to a friend? Yes.
Age: 32 Height: 1.78m Weight: 76kg
I usually ride: All of them! My best bike is: Cervelo Dual
I've been riding for: Over 20 years I ride: Every day I would class myself as: Expert
I regularly do the following types of riding: time trialling, commuting, touring, club rides, fixed/singlespeed, Audax