This is a dash panel retainer. Useful for a variety of applications, it is OE for GM models (1977-present).  It matches GM OE Part Number 25016383. Although this retainer is OE for GM vehicles, it is universal and can be used on any vehicle or application requiring this type of retainer and meeting these specifications.
                                                                                    Material: Nylon
                                                                                    Fastener Type: Single Head
                                                                                    Head Diameter: 7/16"
                                                                                    Stem Diameter: 3/16"
                                                                                    Stem Length: 5/8"
                                                                                    Color: Black
                                                                                    Matches OEM Part Number: GM: 25016383