5/16", Slotted

US Fasteners

Slotted round head

Machine screws

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

Anchoring products

Fasteners for anchoring in stone, concrete, brick, and drywall, etc.
Rivet nuts

Threaded inserts & Rivet nuts

For adding a machine thread to material that otherwise can not be tapped.