ISO 7380-2 Allen Socket Button Flanged Head Screws eliminate the need for a separate washer, distributing tightening force over a greater area.
Class 10.9 Hardened Flange BHCS are a high strength fastening solution with a black oxide finish that provides minimal corrosion resistance, best for indoor, dry environments.
Stainless Steel is best for low strength applications that require corrosion resistance in damp environments.