PREMIUM AUTOMOTIVE HEX WASHER HEAD SEMS SCREWSAuveco 12351 M6.3-1.81 x 20mm Hex Washer Head SEMS Screw with 17mm Washer – Black Polyseal Finish. Head Type: Hex Washer Head SEMS. High-quality automotive fastener designed for secure fastening of body panels, splash shields, trim components, and engine bay parts.