Filters: 5/16" US Steel Zinc 3-1/2" External hex Hex Remove All

5/16" x 3-1/2", US, Zinc plated steel, Hex head

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.
Lag bolt

Lag bolts

Large wood screws technically called lag screws.