4-40 x 1 Hex Machine Screw 18-8 SS

4-40 x 1 Hex Machine Screw 18-8 SS . A straight shank fastener with external threads designed to go through a hole or nut that is pre-tapped to form a mating thread for the screws. Machine screws form a fastening superior in strength to spaced thread screws. These stainless machine screws are ideal for environments where corrosion is an issue.