ASTM A453 Grade 665 Full Threaded Stud Bolt Plain Color Metric Stud Bolt

A stud is essentially just a piece of threaded bar. This often resembles a
machine screw without a head, although some studs to have heads that get
permanently incorporated into the part they are attached to. Studs are often
designed to be permanently attached to one part, proving a means of attaching
another part in conjunction with a nut. This type of stud may be welded, swaged
or bonded to attach it and may, therefore, have a small head to enable this.
Other studs may have threads at both ends. In some cases, these are both intended
to accept nuts — such a stud is called a stud bolt. Alternatively, a stud may
have a self-taping thread at one end, intended to be permanently screwed into a
part, and a machine thread at the other end to accept a nut

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