The extension to allow the Kong light to be helmet mounted provides a firm connection and the uncoiled version is the right length but the cable it hard to detach from the light. This gives the firm and reliable connection but for my arthritic hands it is hard to get apart.
I haven't had the chance to use it, but it seems great. The advantage is the battery is no longer on your head (making your neck sore, or sloshing your helmet around) and can be carried in a pack. The curly cord could afford to be a little longer though because it only stretches easily to my upper shoulders region, and there aren't a lot of packs that have pockets that high.
PWR Helmet Extension Mount
I have ordered several lights and other knog products. I have nothing but great things to say!! You cannot go wrong with Knog, it is spot on!!
Could reduce the battery weight on helmet or on bar mont effectively.
Maybe 10 more cm would be great in lenght.