New bases are fitted with new shafts, throttle blades, idle mixture screws, springs and has the large center carb throttle arm attached.
If you have a vacuum leak around the throttle shaft you may only need to replace the throttle shaft because it is worn and not the entire throttle body. Also have the front and rear 59-66 end carb throttle bodies on the web page and the large 66 center throttle body. Comes with the necessary gaskets.