Shoulder Screws and Nuts are a piece of hardware that Dell typically uses to attach the slide rail kits to the chassis. The shoulder of the hardware drops into a notch on the inner tract of the slide rail assembly. This makes the installation of the rails very fast and easy.
The threads of the Shoulder Screws & Nuts are 10-32. The Shoulder Screw is 7/16″ long. Dell Shoulder Screws & Nuts are proprietary hardware and cannot be purchased at a Hardware Store. However, using standard machine screws and washers it is possible to duplicate the method.