Socket Head Cap Screw - strongest of all head style.

• Head height is equal to shank diameter.
• Shouldn't be mated with a regular hex nut, which isn't as strong.

Low Head Cap Screw - designed for applications with head height limitations

• Head height is approximately half the shank diameter.

Flat Head Cap Screw - for flush applications

Caution: Inch and metric have different countersink angles. Mismatching fastener and hole countersink angles can result in premature fastener failure

Button Head Cap Screw

• Larger head diameter makes it more appropriate for holding thin materials like sheet metal guards.
• Because of its internal hex drive style it's ideal for tamper-proofing applications.
• Good substitute for other drive styles that are prone to stripping like Phillips and slotted.

Socket Shoulder Screw

• Typically used as a pivot point or axle because shoulders are ground to a tight tolerance.

Thread Class

• Socket head cap screws 1" diameter and under have class 3A fit (tight tolerance). Over 1" have a class 2A fit (typical hex cap tolerance).
• All other head styles and diameters have a class 3A fit.