This product functions effectively and emits a very intense light; exercise caution to avoid direct eye contact. The brake light is exceptionally bright and operates correctly.

The light is super bright, really annoying if you look at it directly. It's very effective at braking. However, I don't give it 5 stars because the battery life is very short, only 3 hours, which isn't enough for a round trip on some routes.

The lack of clear instructions for selecting a mode is a problem. However, the product is well-made, and the light is very bright.

The brightness and small size are impressive. While I don't know if it's durable enough for extended use, it's ideal for my daily travel.