SERFAS THUNDERBOLT 2.0 REAR LIGHT

Super Bright (50 Lumens) Daytime Flash
Auto Safe Mode, Last Mode Memory
USB Remote Switch Compatible
USB Rechargeable
Solid Modes: High (25 Lumens): 1.5hrs, Medium (15 Lumens): 2.25hrs, Low (10 Lumens): 5.5hrs
Flash Modes: *Daytime Flash (50 Lumens): 19.5hrs, High Flash Slow (25 Lumens): 9.5hrs, High Flash Fast (25 Lumens): 5hrs, Low Flash (10 Lumens): 13hrs, Auto Safe Mode Extends an Additional 45mins
Weight: 40 Grams with Bracket
Battery: 500 mAh Lithium Polymer