This is a Wonderful light. Used it for over 2 hours straight brightest setting and the battery still had plenty of juice left. I use it for riding in the evening, one evening it started to rain and there was no issues it was just fine. After riding in bike lanes, this light is brighter than most passing cars and trucks... no worries you will be seen! Metal is made of bigh quality grade aluminum so it wont rust or break like cheap plastic ones. Each module is sealed with a rubber o-ring and the usb charge port is sealed with a tight rubber pad, perfect! This headlight doubles as a flashlight when not on bicycle and goes with me where ever I go, the back lights are also bright you can have them solid or flashing.. Love it!