From a user's perspective the dynohub works just like a normal front hub, except it has an electrical connector on one side that outputs juice when you're rolling. Maybe this is what looks like a "locking mechanism"? Anyway, the dynohub is a hassle initially because you have to have your wheel rebuilt around it, but after that it's fantastic because you never have to carry batteries or worry about how much charge they have left. Light selection is more limited than battery-powered lights, but there are some great dynohub lights available.