5-1/2", US, 13

US Fasteners, 5-1/2", 13
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.	Machine screws Screws with machine threads for use with a nut or in a tapped hole.
Carriage bolts & Plow bolts Bolts with no drive and machine threads for use with a nut.	Socket screws Screws with an Allen wrench drive.
Studs, Rod & Stock Studs, threaded rod, unthreaded rod and keystock for industrial, machining and manufacturing applications.	Anchoring products Fasteners for anchoring in stone, concrete, brick and drywall, etc.
Shoulder bolts Screws with an unthreaded shoulder that is larger in diameter than the threads. Also known as stripper bolts.