Rod end bearing is a mechanical articulating joint used on the ends of control rods, steering links, tie rods, or anywhere a precision articulating joint is required. These joints are particularly useful where a clevis end requiring perfect 90-degree alignment between the attached shaft and the second component is unsuitable.
A ball swivel with an opening through which a bolt or other attaching hardware may pass is pressed into a circular casing with a threaded shaft attached. The threaded portion may be either male or female. The heim joint's advantage is that the ball insert permits the rod or bolt passing through it to be misaligned to a limited degree to an angle other than 90 degrees. A link terminated in two heim joints permits misalignment of their attached shafts.
Metallic rod end bearings are made of brass, bronze, iron, or steel and often plated with zinc or chromium.