12-Point Screw

A 12 point screw is a bolt with a twelve sided head, also known as a ferry cap screw. It allows high torque to be applied in tight spaces.

A 12-point screw has a twelve-point head that takes a matching socket or ring spanner. It is used where high torque and a compact head are needed, often in power generation and heavy machinery. It takes a nut of the same thread and class, and often a washer.

This kind of screw is often made in stainless steel 316 or high temperature alloys. Stainless steel 316 gives good corrosion resistance. High temperature alloys are used where the joint sees heat.

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

Ask for a mill test certificate to confirm the material and mechanical properties. On receipt, check the head for cracks and the thread for damage. Verify the dimensions with a gauge if the fit is critical.