I actually have this (paid a little more) and it works well. It's the same exact light that sells elsewhere on Amazon for $20+ (albeit those come with a cheap taillight worth ~$1).
400 Lumen CREE XPG LED
4 modes: Auto-sensing, Low, High, Red (for taillight)
Micro USB charging port
Waterproof / resistant
NOTE: Comes from China thus takes a while to reach you e.g. 2 weeks+. And limit of one per ACCOUNT ;-)