Most stable quick-release wrist on this planet for body powered prosthetic arms.
While it is relatively expensive to build, it outlasted many other quick-release wrist connectors here without wiggle or decay, and if large amounts of dust or sand are kept away it is relatively service free - after a few years, it is recommended to disassemble it for cleaning. As I am active in an area where I otherwise went through commercial quick-release wrists like on a 3-4 month interval basis, a five-year total cost turned out to be lower with this device, which is why insurance pays for it here. If one hardly ever uses one's prosthesis and does not put significant physical load on it, then it might not be the right thing.
Usage demonstration video:
[12/2010] The German MyHandicap foundation publishes an article about how this wrist came into life.
Historically, we started with helicline mechanism. Then we built the ball lock wrist.
Disclaimer: I have no financial gains or income with this product whatsoever. It is built and sold on request by Roman Meili at MDP Meili AG / Vorma GmbH. My PUPP+CH+EN wrist units here were paid for by insurance.