The Bike List

Blackburn Mars 3.0 rear light £20

Tested by Neil Watterson, tester for The Bike List

Rear lights are rear lights, aren't they? Well, sort of. Almost all of them use LEDs to illuminate, most have a 'belt' clip as well as a bike bracket and most have steady, flashing and alternating modes. So why not just buy the cheapest you can find?

Well, there's nothing wrong with that - it's better to have a light than none at all, but all it will be is a marker light, showing where you are. It may not actually alert other road users to your presence - which on our busy streets you really need to do. You need to stand out against a backdrop of competing lights, so anything you can do to make yourself more visible is worth it.

Take this Mars 3.0 from Blackburn. The company says it has 'seven super-bright, optically enhanced LEDs'. But unlike most lights only five of them are red and rear-facing - the other two are amber and point sideways. So you're visible from the sides as well as the back.

It could be argued that your legs will obscure the side LEDs when the light is clipped to the seatpost mount, but it doesn't have to be used on the seatpost - it comes with a bracket allowing you to mount it in place of a reflector on a pannier rack or it could be on your backpack - in both places it will show up more. That's once you've got it fitted, of course.

The box proclaims it's a 'tool-free' design. And while you may be able to connect the bracket to the bike and the light to the bracket without tools - the bracket is secured with a large thumbwheel Jubilee clip style - you need a screwdriver to adjust the angle of the light.

What's more, you have to remove the light to adjust the aim - so I've found it more of a faff to attach than a standard 'tools-required' light bracket. Anyway, how often do you actually remove the entire bracket from your bike? I tend to fit and forget.

Despite there being two types of bike mount supplied, you can only have one up and ready at a time as they both use the same slide-in section. Which you have to undo with a screwdriver. That said, you could have the bases attached to two bikes and swap the slider units over fairly easily. Anyway, most people will only really use one or the other.

The inclusion of the pannier mount is quite handy as I find my seatpost-mounted light can become obscured. I appreciate that it means I'm ditching the rear panier mounted reflector which should be fitted, but I'd much prefer to have a light that will make me stand out rather than following the law to the letter. I suppose I could just relocate the reflector to the seatpost…

My only other gripe is about the tapered belt clip. I suppose it shouldn't really be about the clip itself, more that bag manufacturers should start to accommodate this type of clip - Halfords uses tapered clips on their lights now and so does this - but my, admittedly couple of year old, bags have light loops that are just too small for the lights. I could make them bigger, but then that may compromise the bags' integrity.

The light output is very good and you'll certainly be seen. The spread is such that it will fill a side of a road at about two car lengths - and as you approach the light it's still clear, thanks to the lens 'bending' the light. And claimed battery life is good too - 50 hours on steady and 150 hours on flashing. I'm guessing that the 150 hours is achieved when the LEDs are illuminating sequentially, rather than all flashing simultaneously - but, as a car driver as well as a cyclist, I don't like seeing single lights being used in this mode; it's simply not as easy to pick out (use it on steady or 'all' flash instead).

Anyway 50 hours on steady is a good runtime - it's over two months' worth of 30 minute commutes, so you'll only be replacing the two AAA batteries a couple of times a year.

So, is it worth buying? I guess the acid test is whether I'd use it as a sole rear light on my part urban/part rural rides - and the answer is yes. If you're after a light to help you be seen, especially if you have a pannier rack, this could just be the light for you.

Buy from

At a glance

Verdict Not tool free as claimed, but versatile, bright and includes a pannier mount.

Blackburn says:

  • 5 Super-bright red LEDs
  • 2 Amber side LEDs for side visibility
  • Steady, flash and chase modes
  • 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

Supplier: Zyro Ltd, +44 (0)1845 521 700,