Running a bar mount dynamo light, and want it sorta in front of your stem, rather than off to one side? This is THE headlight mount for you. The Busch and Muller 'Aluminum headlamp holder' is hinged, so it's super easy to install. Comes stock for 31.8mm bars, IE most mountain and road bars these days. There are shims for you old schoolers running 25.4 mm bars, IE old mountain bike standard, back when Unwound came out with 'Repetition'. This light mount takes up less real estate than the Schmidt mount. We like the Schmidt one, a lot, but this one has it's place too. Get it if you wanna offset the lamp left or right OR need every millimeter of bar space for other contraptions. It's 11mm wide without shims, a shade under 16mm wide with the 25.4 shims. Off road worth, even with a heavy light. Comes with everything you need, even the light mounting bolt.