Hex cap screws feature a washer face under the head and a chamfered point, whereas a hex bolt does not have a washer face or chamfered threads. They are made of low-carbon steel and are very common in construction or repair projects.
Inserted into receiving holes, dowel pins hold together parts of an assembly with friction. They may also be used as location pins. These pins are common in the automotive and aerospace industries as well as in furniture making.
Lynch pins are often used to keep a wheel in place on its axis. These pins may be found in agricultural settings, and like hitch pins, are used to secure vehicle trailers.
Jam nuts are used as a second nut threaded over a bolt to prevent the first from loosening, or in applications where there is not sufficient space for a standard nut.
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