Overview

• Flat head types have flat surfaces that taper toward the screw body to allow for countersinking
• The flat head lies flush against the workpiece
• Machine screws without washers can be used with both flat and lock washers
• Spanner drive types feature two holes on the head designed to provide security and prevent tampering
• Spanner fasteners require a special driver to tighten or loosen
• Stainless steel is a strong, corrosion-resistant alloy with excellent resistance to heat
• It is used in high-stress, outdoor and corrosive applications.