I drew and posted this part because we used it in our design this year. I'ts available from McMaster-Carr.
FirstCadLibrary is not an official FIRST sponsored site. It's a site I created to help all those FIRST teams who want to use the donated Inventor software to design their robots without having to spend countless hours drawing common parts. The "Manufactured" library are parts that we designed for use on our robot over the years (I'm a member of team 34).