Main Features: Excellent durability: The Recognition Helmet flashlight operates in two modes, including normal glow mode and flashing mode Easy to use: you can hang your flashlight from your backpack, attach it to your helmet, attach it to your bike seat, or drape it around your neck. CR2032 button battery: it can last for one week in steady on mode and one month in flashing mode (the actual time will vary according to the ambient temperature).The battery can be replaced by itself after use, but it needs to be replaced by cutting the silicone, so as to lose the waterproof wrap and pay attention to the edge of the battery to avoid the contact between positive and negative electrodes. Specification: Material:Silicone,Resin Size:11cmx2.6cm Color:BlackRed,BlackBlue,BlackGreen,BlackWhite,BlackPurple,BrownRed,BrownBlue,BrownWhite,BrownPurple,BrownGreen Lighting Mode: Always On, Flashing Battery Model: CR2016 Waterproof Rating: IP6 Package Included: 1Pc x Helmet Light Note: Please allow 1-3cm differences due to manual measurement. Due to the difference between different monitors,the picture may not reflect the actual color of the item.Thank you! No Retail Box,Packing Safely in Bubble Bag.