Case-hardened and black oxidised. Note: Positioning feet are used as supports, stops and thrust pads for fixtures and general machine and appliance construction. Drawing reference: Form A: External thread and flat face Form B: External thread and convex face Form C: External thread and serrated face Form K: External thread and carbide serrated face Form L: External thread and POM insert Form D: External thread and flat face Form E: External thread and convex face Form F: External thread and serrated face