Review on 🔦 4-Pack LED Safety Light - Reflective Gear Accessories for Runners, Kids, Joggers, Bikers, Dogs, Walkers - Ideal for Nighttime, Cycling, Bicycle Travel by Travis Rio

After only 32 hours of use (I estimate I've had one of these on for that many hours since purchasing it in April) the batteries are dead. To replace the battery you have to use a tiny screwdriver (which they provide) to remove the four tiny screws. Then you need two CR batteries, which I don't keep around the house (and I guess I'm typical). Add to that the light isn't particularly easy to turn on and off (press the little tiny button, press again and repeat to turn it off), sorry I wasted my money. They're definitely lightweight, so if that's what you're looking for and don't mind working with microscopic fittings, then they might be for you.