Black Oxide 18-8 Stainless Steel is used on black tools, gun builders and car and motorcycles looking for that black sleek look. These fasteners are chemically treated to create the back oxide finish and are finished with wax. Phillips Pan Head Machine Screws are driven with a Phillips bit. Black Oxide Stainless Steel fasteners have clean heads with no stamping or marking for a nice clean finished look. A Phillips Pan Head Screw, also known as a Machine Screw, Phillips Screw or Machine Screw Bolt.