Button Head Socket Cap Screw

A button head socket cap screw is a screw with a low domed head and a hexagonal socket. It is tightened with an Allen key and gives a neat, low profile finish.

A button head socket cap screw clamps parts where a low, rounded head is wanted. It takes a hex key and often a nut or a tapped hole of the same thread and class.

Zinc plating gives a zinc coating for mild corrosion resistance. Black oxide gives a dark finish with slight corrosion resistance and is often used on tooling. Plain finish has no added coating and suits indoor or controlled environments.

A button head socket cap screw is often made in stainless steel 304 or stainless steel 316. Stainless steel 304 suits general fastening, while stainless steel 316 gives better resistance to corrosion in marine or chemical settings. The screw can also be made in alloy steel for higher strength.

This is a general guide to checking this kind of part. It says nothing about any supplier's parts.

Ask for a certificate of conformance for the material and grade. On receipt, check the socket for damage and the thread for burrs. Confirm the head marking and dimensions match the order.