NiteRider Sentinel 250 rear light with Laser Lane modes

The NiteRider Sentinel 250 is a brighter version of the regular Sentinel light tested previously on road.cc. It packs the same lasers, creating a unique virtual cycle lane, but ups the brightness to a whopping 250 lumens. It's easy to use, provides several modes and the battery life is good, but I'm not convinced that the lasers bring much benefit.

• Pros: VERY BRIGHT, lasers, battery run-time
• Cons: Lasers, bracket, buttons

The unique appeal of the Sentinel, and really the main reason you'd buy it over any other light, is the pair of lasers which create a virtual cycle line behind your bike. There are three modes of lasers, and you can choose to activate them on their own or in conjunction with the two main LEDs.

> Find your nearest dealer here

Ride or drive behind a cyclist with the Sentinel and you'll see two long lanes projected onto the road behind and alongside the rear wheel. The width and length of the lanes are dictated by how you mount the light to the bike. The idea behind the lasers is to suggest to other road users that they pass at a safe distance. In my experience, riding in both rural and urban environments, I didn't feel any safer than with a regular rear light. Close passes still occurred despite the lasers flashing a path behind me.

What certainly seems to get motorists' attention is the whopping 250-lumen output. That is seriously bright for a rear light. Skip straight down to the comments section if you want to join in a debate about how bright is too bright.

You can choose from two flash and two steady modes, the latter providing high and a useful group ride mode that ensures you don't blind your mates. There's also a daylight visible flash mode, as is increasingly common with rear lights for those cyclists interested in running lights during the day as well as at night.

> Buyer's Guide: The best front lights for cycling + beam comparison

The Sentinel is well made and is IP64 dust and water-resistant. It has stood up to a couple of rides in the rain, getting subjected to lots of mud, and my very unscientific hosepipe test.

The two rubber buttons are fiddly to use with big gloves; perhaps separating them would provide easier use?

Battery life is good and on the money, with a minimum 5hrs if using the main light on a flash mode without a laser, up to 45hrs on a steady beam and 11:30hrs for the lasers. There's a low battery indicator when you turn the light off – the centre circle lights up red if the battery is low. The light is easily recharged via a USB cable, taking just 3hrs.

> Buyer's Guide: 16 of the best rear lights for cycling

The bracket comprises a silicone band that is familiar and easy to use, and went onto a few different bikes including an aero seatpost with no problems. What is a problem is how flimsy the main bracket is; the light moves up and down too easily, and on my first outing the weight of the light caused it to pivot down and project the lasers onto my legs! You have to tighten the crosshead screw a lot to get it to stay firmly in place. On the plus side, it never came loose but I'd prefer a better designed bracket at this (or any) price.

It's a smart and clever design but I'm not convinced the lasers provide any actual road safety benefit, which leaves just an extremely bright light with good battery life but a flimsy bracket. Add in the £55 RRP (cheaper if you shop around) and it's pricey too. If you don't need 250 lumens, there are some excellent cheaper options, such as the Exposure TraceR Daybright and the Blackburn DayBlazer 65 Rear, to name but two.

Verdict

A smart light, but expensive and there's little sign that the lasers offer any real safety benefit