6, 3-1/2"

US Fasteners

Hex bolt

Hex bolts

Bolts with hexagonal heads and machine threads for use with a nut or in a tapped hole. Also known as hex cap screws or machine bolts.
Socket product

Socket screws

Screws with an allen wrench drive.
Nut

Nuts

Nuts have internal machine threads, for use with machine thread bolts and screws.
Eye bolts

Eye bolts & Screw eyes

Bolts or screws with a circular ring on the head.