I have a harness running light but was looking to replace a head band light that I made smaller to fit on my upper arm. The head band light takes 3 AAA batteries, and is a little heavy. I attached this light to an arm band, and it works fairly well, but the beam can't be directed, so it shines straight ahead. I want to see the ground in front of me, and there is no easy fix to direct the light. It's pretty bright, but not as bright as my harness light, or a spot head light.See full review