1/8"

US Fasteners

Machine screw

Machine screws

Screws with machine threads for use with a nut or in a tapped hole.
Socket product

Socket screws

Screws with an allen wrench drive.
Set screw

Set screws

Screws with no head and machine threads for use in a tapped hole.
Spacer

Spacers

Unthreaded sleeves that fit over bolts or screws to maintain space between components.
Sex bolt & Mating screw

Sex bolts & Mating screws

Sex bolts resemble machine screws, but with internal threads, and can be used with either specialized mating screws or standard machine screws. Also known as barrel nuts and Chicago bolts.
Shoulder bolt

Shoulder bolts

Screws with an unthreaded shoulder that is larger in diameter than the threads. Also known as stripper bolts.