I ride almost exclusively at night. I have three wheels built up with dyno hubs. But on those occassions when I rode a bike that didn’t, I used an ultrafire wf-502b flashlight that uses an 18650 rechargeable battery. its bright, cheap, lasted well over any 20-35 miler i did and a spare battery is easy to carry. It mounts easy and is easy to remove. Unless its a dyno light I will never purchase a specific bike light again. Best of all its only 25-35 to get one with a good 3500mAh battery and the mount… much cheaper than most battery lights sold for bikes.