Zefal Supervision R150 Rear Light

The Zefal Supervision 150 rear light is a five-mode model producing a maximum of 150 lumens but with sensible options for most riding conditions. There are the features we've come to expect, plus a couple of pleasant surprises – and the odd quirk. It charges quickly, and a really positive switch means you'd have to be going some to find it powering up when bouncing around in a bag. As is becoming more common, Zefal hasn't included a charging cable with the light, but most of us will have a stash of USB C cables for phones and other tech.

Specification

Measuring 78x47x28mm and tipping the scales at 73g, the Supervision is made from a reassuringly solid-feeling plastic. Behind the long broad lens (reckoned to project a 270-degree arc of light) live two traditional diodes, rather than the commonly accepted COB (chip on board type).

The on/off switch in the centre of the light is firm and requires a three-second press to power up. It caught me out first time round – I thought the 3.7V 1,200mAh lithium polymer cell wasn't charging. However, it's easily found in the dark, even wearing full-finger gloves. Alternating between the steady and flashing modes is just a question of prodding the switch twice, and then a single prod will change the output. It has a memory function too, adding to the convenience.

It works as a battery life indicator too, showing clear when fully charged, red at 50%, and flashing red when charging.

Zefal has hidden the charge port around the back behind a sturdy silicone panel. It's easily accessible and the cover is a very secure, fit – so much so I've not felt inclined to put a dab of grease on the port cover, even when mounting it low on the chainstay or on my trailer.

This tallies with its IPX6 rating for weatherproofing – the light should resist 'power jets of water from any direction' – and it's been caked in wet, gloopy filth along country lanes and used in torrential rains and has never missed a beat. It's also survived being left in situ when I gave the host bike a deep, sudsy bucket scrub.

Mounts

There are two mounting options – a bag/clothing clip affair and a large silicone 'watch strap' type. The strap needs a bit of gentle stretching before use, but is secure on thinner tubing, such as seatstays, and on seatposts – I had no issues with 25.4mm through to 31.8mm, though it won't work with aero designs.

As for the bag clip, I've found it quite versatile and reliable on jersey pockets and light straps common to panniers and wedge packs.

Performance

Output, though not as retina scorching as some COB units boasting similar firepower, is nonetheless impressive.

Its five modes consist of three steady (80, 50 and 15 lumens) and two flashing (150 and 50lm), which cater for everything from the darkest, wettest nights, to congested town centres and group rides.

Though not marketed as such, the 150-lumen flash is more than up to the job of a daylight flash. Even in strong autumn sunlight, other riders reckoned they could spot it from 125m. At the opposite end of the spectrum, during a very wet, dark night ride, fellow riders reckoned they could see it at 350m.

I also mounted the light on my low-slung trailer and it seemed to do a decent job of keeping it conspicuous to approaching traffic. I alternated between the 150-lumen and 50-lumen flash – the latter for town, or when I've needed to conserve some juice. Along pitch black roads, a neighbour reckoned they could spot the 50lm flash and trailer at a good 100m, citing the distinctive pace, and I've had no issues seemingly staying on the radar when negotiating bigger roundabouts.

The 15lm steady mode is the sort I'd run on an evening group ride or in town. It strikes a nice balance between presence and run-time. Other traffic seemed to take notice at 25-30m through suburban and town sections, and on clear nights, approaching riders reckoned nearer 40m.

The 50-lumen steady is the better bet for dark, unlit sections, overkill for town and group rides, although it hasn't raised heckles on occasions where I've forgotten to nudge down. It's visible to around 70-80m along country roads, 40-45m through town with competing illumination.

The highest 80-lumen steady is impressive – consultation suggests it's visible on dark lanes to 125m; heavy rain saw this dip to around 80m, but it's very conspicuous just the same. The trade-off, of course, is run-times.

Run-times

These seem very faithful to those cited by Zefal, at least in temperatures between 4 and 12°C. It's returned 2:53hrs from the 80lm steady, 5:25hrs from the 50lm steady, and a cell-sipping 15:54hrs from the 15lm steady. The 150lm flashing has returned 7:54hrs and the 50lm flashing 15:56hrs.

One thing to note: there's no auto kickdown for when reserves dwindle.

Charging lives up to the claims, taking a convenient two hours zero to hero when plugged into a computer USB socket, around 10 minutes quicker from the mains.

Value

If you're seeking a simple yet powerful rear light, the Supervision 150 has quite a bit to offer for its £49.99, if a bit pricey perhaps considering it has no sensor technology.

For example, it's the same price as Ravemen's TR200 Smart Alert with Brake Detection, which also includes a choice of mounting options, including aero seatposts, though the two 100-lumen flashing modes might be a bit restrictive if you wanted a town sensible flash, and the 5-hour charge time could be a turn-off.

It's also a quid more than Magicshine's Seemee 300 Smart Tail Light, which generally impressed Stu last year, who described it as 'a bright light with some clever functions'. And the Seemee 200 Version 2, which I reviewed back in 2023, is over a tenner cheaper at RRP (and currently £36.99), with clever optics and intelligent modes. There's a 10lm steady and group ride mode alongside a more potent 60lm steady, and a smart function that lets the light adjust output between 10 and 60lm. The 'braking function' increases intensity progressively but will put a dent in run-times, though it can be switched off.

For more options, check out our guide to the best rear bike lights.

Conclusion

There are competitors offering higher levels of sophistication – 'braking' functions and similar sensored tech – for less cash, but nonetheless, the Zefal Supervision 150 is a powerful, user-friendly light well suited to the darkest nights.

Verdict

Capable light with decent output, battery life and charge times, if a little pricier than some