Go back and read Toms last post. He made a mistake; he did not know that Hitec had a new xtra HD arm. several are using them with no problem whatsoever. They are two thick and sturdy to twist. I use them with the new Dubro 899 HD balllink and H9 titanium pro-link shafts connecting to a Nelson Hobby Rocket city clevis on the control serface. a little pricey but an awesome setup.