Brass Hex Bolt with collar

These threaded machine bolts, sometimes referred to as hexagonal head bolts or Hex Bolt With Collar , are used with nuts or in tapped holes. Hex head bolts, as their name implies, have brass heads that are hexagonal (6 sides).

Hex Head Bolts Head & Thread Dimensions

Technical dimensions for the head and threads of all grades and materials of hex cap screws. Body diameter, width across the flats, width across the corners, head height, and thread length are considered technical parameters.

There are two varieties of hex head bolts: completely threaded and partly threaded.

When a completely threaded hole and a fully threaded hex head bolt are compatible, the latter is utilized.

In order to increase holding strength when force is applied to the structure being fastened, partially threaded bolts are more stiff and have a section under their heads that is not threaded.

Hex Head Bolts are not Hex Cap Screws

Mistaking a hex cap screw for a hex bolt is very common, but the two fasteners differ in many ways, including how they are used and installed.

Hex bolts are installed by turning a nut to tighten the fastener. Hex cap screws are installed into tapped holes by turning the head to assemble and tighten.
Hex bolts have neither the washer face nor chamfered point. Hex cap screws feature a washer face on the bearing surface and the chamfered point.
Hex bolts are often used in the construction industry, where mechanical properties are more critical than dimensional tolerances.Hex cap screws are commonly used for precision applications where tight tolerance is required.