Serfas Thunderbolt 2.0 Tail Light Bicycle Night Riding 7 Modes 50 Lumens

• Super Bright & Actually Works - 50-lumen Daytime Flash mode cuts through traffic and bright daylight. Real-world riders say it’s "seriously visible" - cars notice you faster, even from a distance.
• Battery That Doesn’t Flake Out - Solid modes last up to 5.5 hours, flash modes up to 19.5 hours. And if you forget to recharge? Auto Safe Mode kicks in to squeeze out another 45 minutes, so you’re not left in the dark.
• Lightweight, Tough, and Easy to Use - It weighs just 40 grams with the mount. Reviewers love how it mounts quickly, stays put, and survives rough, everyday riding without breaking.
• USB Charging + Remote Compatible - No batteries. No hassle. Recharge it like your phone. Plus, it can hook up to a USB remote switch if you want easier control while riding.
• Built to True Series Standards - we didn’t just guess at the lumen output, these lights meet and beat the advertised brightness. Reviewers back it up: you will notice a big difference versus cheaper lights.

The Serfas True Series tail light is built for riders who demand real performance. With a 50-lumen Daytime Flash, Auto Safe Mode, USB rechargeability, and aero post compatibility, it’s lightweight (40g) but heavy on power. Solid modes last up to 5.5 hours, flash modes up to 19.5 hours, and an extra 45 minutes with Auto Safe Mode. Trusted by riders for exceeding lumen claims, it’s the light that turns night into day — and keeps you seen.