Excellent durability: The Recognition Helmet flashlight operates in two modes, including normal light mode and flashing mode, and the helmet light uses a built-in CR2030 battery for about 100 hours of operation. Waterproof: The helmet flashlight is made of high quality silicone and gel with good sealing (water resistance) and flexibility. This product can work well in -20~ 50 environment. Versatile: This flashlight is essential for outdoor activities such as biking and hiking. 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. Tip: When the battery runs out, you can replace the battery yourself (but replacing the battery will affect the waterproof function of the product). Specifications: Size: approx. 11cmx2.6cm / 4.3inx1.3in Materials: silicone, resin Application: Camping, hiking, mountaineering, biking, etc. Lighting mode: Always on, flickering Battery model :CR2032 Battery life: up to 100 hours Waterproof class :IP67 Packing list: 1* Helmet flashlight 1*CR2032 Battery (built-in)