I use a simple Eveready 7 LED flashlight on my helmet as a "supplimentary "be seen" light. I purposely picked something around 120 lumens so I don't blind drivers. I use an elastic hair band through the helmet's vent holes to hold it, and a rubber washer around the front of the flashlight to raise the front to aim higher. It is perfect for seeing my cyclocomputer at night also since its modest light doesn't make my eyes re-adjust. Three AAA lithium batteries last me 25-30 hours.