The Serfas True Series light line was developed to be the best on the market.
Given the True stamp of approval, these tail lights will meet & exceed their expected lumen output while offering you all the features you’ve come to enjoy from Serfas lighting.
Our fist look at the new Thunderbolt was impressive. Serfas have improved the Thunderbolt for the new year. Light power is still awesome but the new bracket system is great. Mounts to any shape seatpost with no fuss at all.
Super Bright (50 Lumens) *Daytime Flash
Auto Safe Mode
Last Mode Memory
USB Remote Switch Compatible
Aero Post Compatible
Solid Modes: High (25 Lumens): 1.5 hrs, Medium (15 Lumens): 2.25 hrs, Low (10 Lumens): 5.5 hrs
Flash Modes: *Daytime Flash (50 Lumens): 19.5 hrs, High Flash Slow (25 Lumens): 9.5 hrs, High Flash Fast (25 Lumens): 5 hrs, Low Flash (10 Lumens): 13 hrs, Auto Safe Mode Extends Runtime an Additional 45 mins