This is a genuine Porter Cable replacement part, it is sold individually. A Cord Strain Reliever is used on most all power tools. It purpose is to reduce the bending of the cord as it comes out of the housing, which otherwise would cause the cord to crack and wear.
It is a genuine replacement screw that is supplied directly from the original equipment manufacturer, it is commonly utilized on Black and Decker and Porter Cable routers. This part generally secures the wear plate, please refer to the appropriate diagrams of your model for the correct location and application of this hardware. It is a high-quality Torx screw which is sold individually.