Overview

• Hex washer head types have a metal washer at the base of the six-sided head that distributes stress and protects the workpiece surface finish
• 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
• Steel is strong and durable but less corrosion resistant than stainless steel
• To improve its resistance to corrosion, it may receive additional finishes and coatings
• Type B screws have large, flat points and a fine thread pitch
• They are used to cut threads in heavier sheet metal
• They can also be used in blind holes.