Splitting the difference between the previous Flux 800 and 900, the Flux 850 gets the game-changing Mode Shift found on the Flux 1250. This means there are three steady modes, all using both the wide and spot beams. Go from Steady Low to Steady High in a single push, without cycling through a flash mode. Press-and-hold for two seconds and you get into the secondary modes: Steady Flash to be seen in busy urban environments, Flash Mode for endless runtime, and two Flashlight modes with 10 and 20 hours of runtime for hanging around the campsite, or when you forget to charge your light and need to conserve the last few percent of battery life to get home.

IPX7 waterproof means this light can survive being submerged 1 meter deep for 30 minutes. No, it's not meant for scuba diving. But is can handle anything you can throw at it on two wheels.

• Sculpted double beam pattern uses separate optics for wide and spot beams to put light where you need it and maximizes every lumen. The result is a beam pattern that torch-style lights can't touch.
• 1x CREE XP-L High Intensity LED plus 1x CREE XP-G LED.
• Quick-release bar mount works on 22.2, 25.4, and 31.8mm bars to put the light above, below, or in front the stem to clear cables and computer mounts.
• Extra bright side lights to give you 180-degree visibility to other cyclists and motorists.
• 2600mAh Li-ion internal battery is USB rechargeable via included micro USB cable.
• Depending on mode, up to an additional three hours of super-low output are available when listed runtimes expire. Trust us, someday you'll need this.
• Steady High mode: 850 lumens for 1:30 hours
• Steady Medium mode: 450 lumens for 3:00 hours
• Steady Low mode: 250 lumens for 6:00 hours
• Press-and-hold to turn off, long press-and-hold to enter secondary modes.