This is a genuine replacement part sourced from the original manufacturer for use with power tools. The metal screw is commonly used with several different types of power tools, and the application of the screw can vary based on the model of the power tool. This screw is available as an individual replacement part, please see model diagram for part location and usage.
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.