normal caliper brake on rear wheel. The sad thing is that I had a mini highwheel before with 27" front wheel, 12" rear. The front hub got trashed just by normal riding. I tried making it a fixed-hub, but no luck. So I eventually scrapped the frame/fork. Proving again why I should never throw anything out. So now using the bearing carriers from the green machine, I will have to build a new fork, and bend a frame myself. I have a tubing bender, but it was basically half of the kit ($10 at flea market). Has the main mech and dies, so I'm building a stand, adapting a solid shaft from an old furnace fan, and found a wheel at the salvage large enough to use to turn the center die. Having 20 spokes makes the wheel look more basic. Not sure about strength though, but it's a stout rim. Might try it as-is.