Overview

• Alloy steel is the strongest of all steel types
• It has high tensile strength and offers excellent resistance to wear, fatigue and galling
• Machine screws without washers can be used with both flat and lock washers
• Round head types are dome shaped with flat bearing surfaces
• They have higher head heights than pan head fasteners
• Slotted drive types are used with flat-blade drivers
• They have one linear slot that runs the length of the head
• Drivers must be centered in the slot during tightening or they will slip out and damage the fastener.