I made a video showing how a two speed kickback works. This one has a coaster brake, but the shifting is the same on a regular kick shift hub. This one is Sturmey Archer, but it's the same operation. High gear has pawls that make noise, low is silent. One downside is that when you stop it shifts because you pedaled backwards. Then you start out in high gear instead of low. I've found that if your only bike is a kickback two speed, you get used to it and it becomes second nature. I like this because there are no cables to shift or brake, simple.