ROCKBROS has released a swarm of new bike lights for 2025, featuring automatic brake indicators, auto shutoff, magnetic mounting options, and long battery life, all at affordable prices. But is there a catch? Yes. Let’s take a look.
We’re taking a look at their “Magnetic Smart Tail Light” and their “R0” back and bar end lights. All models feature relatively unique accelerometer based automatic brake lights, which can be set to engage automatically when the cyclist slows down. The Magnetic Smart Tail Light features a convenient magnetic mount, while the R0 models attach using more traditional clip, band and twist lock mechanisms. They can be attached to saddles, seat posts, handlebars, and some packs. They range from $32,99 for the magnetic light, and $29 and $39 for the back and handlebar lights respectively.
Starting with features, I really liked the automatic brake sensing on the models. Essentially, these act like normal bike lights, until the rider slows it. The modes include pulse, strobe solid, breathing action, and similar offerings. However, when smart modes are engaged, it enable the braking functionality. When the bike slows down, it automatically engages and brightens into a solid glow, like a tail light. This is exceptional for groups rides to help riders maintain a safe distance from one another, and can help the rider to be more predictable in traffic situations as well. The same sensor also allows it to automatically turn off to save battery when it no long senses vibrations, and it will turn back on as well. This is handy for short and frequent stops when the rider may not want to have to turn the lights on and off, especially the back ones. The handlebar lights have a clever feature where they can sync with other R0 devices in the vicinity. There is Linkage and Same frequency mode. The former, the host device controls all the other lights in the vicinity. The same frequency mode ensures that all the lights flash or blink at the same time, multiplying their effectiveness. It is quite unique. So, if you have a group of riders who are all using these lights, they all work in unison after a quick pairing session. I couldn’t test this as I don’t have enough units, but the promise is very cool.
Attaching the devices is mostly quite straightforward. The Magnetic Brake Light mount simply attaches via a silicone band that wraps around the seat post. The light itself then simply snaps in place with magnets. It’s incredibly simple and convenient. Removing the light is just a matter of pulling off the light, yet it’s entirely secure. The R0 back light includes several mounts, all of which are easy enough to figure out. The only odd one was the saddle mount, which requires zip ties to secure. It works, and it doesn’t budge, but it’s a little odd to rely on zip ties given they’re single use items (it comes with two sets and they are easy enough to replace). The manual was also terribly vague about how this should be done, and the half inch tall image provided simply said “attach” with no mention of how, or even the zip ties. This was a little strange, especially as a minor tweak could allow the same mount to use the already included silicone bands. But, I figured out this was in fact the way to connect them it by looking at images on the site. Once the mount is installed it looks pretty sleek honestly. The light itself twists and locks into to mount with no issues. So that’s great. Removing it requires pushing in with some pressure then twisting.
When it comes to brightness, these are definitely on the weaker side. They’re advertised as about 100 lumens, but seem significantly dimmer than other devices I’ve tested with the same advertised brightness. They only seem moderately sufficient in this area and only in certain scenarios. They certainly glow and are visible, but due to the diffusion layer on the lenses they have a soft appearance that doesn’t sparkle or dazzle. Great for group rides, but probably not great in busy traffic or solo riding where you want to almost dazzle the cars around you to ensure you are noticed. As I do a lot of solo riding I personally would want a brighter light for visibility, but will instead use these as supplemental lights on the bars, helmet, or the seat, with a brighter light on my seat post. In bright sunlight, these are all but useless honestly. They can be barely visible in full sun and I would not recommend them for this use scenario. A quick daytime brightness demo can be seen below.
Pricing and build quality I’m lumping together here. The prices are quite good at only around $30 to $40 depending on the unit. The build quality that comes along with that price point is exceptional. I’ve easily paid double for lights that are built half as nice as these. They’re dense, rugged, and the mounts all have sturdy plastics, tight seals, and robust rubber mounting pads. The value is certainly there. Long term we’ll have to see how they hold up to rain and sun, especially the bands, but I’ll report back if I find anything problematic later on.
Other thoughts? Switching modes is easy enough, a long press turns them on and off, single press switches through modes, and double presses toggle between smart and manual modes. It includes LED based battery level indicators (below 30 percent) and they charge at a decent clip and do include short USB C cables. They’re all waterproof as well.
Overall
I like the R0 and Magnetic Smart Tail Light. They’re well built, easy to use, and the mounts are surprisingly secure. For my personal usage, which is solo riding, generally in harsh sun, they aren’t very useful. However, for group rides or rides where bike lanes and other bike friendly infrastructure area available, this could be a good option. However, if visibility is a necessity in full daylight, these should be avoided. Still, at this price point, and considering the features and build quality, they can find a use. If you’re looking for something for group riding or don’t plan on soloing traffic heavy areas, these could be a good bet.
