I purchased these lights at my local specialty running store and they were well worth the investment. I do not normally run at night, but I purchased them anyhow so that I could wear them at dawn or dusk, but then I realized that I could wear them during the day, too, so that perhaps the lights would catch a driver's attention as I crossed streets. Already two cars slowed down when they saw me, so I think they are also effective for day running. If anything, it gives me comfort knowing that perhaps the moving lights will be noticed. The product is easy to use, and I like how there are 360 degree lights (there are red lights so that a runner can be seen from behind as well). I especially like that they are weather proof and rechargeable. I would definitely buy them again or would buy them as a gift.