What type of fastening device is an M8 hex head bolt?

An M8 hex head bolt is classified as a type of bolt because it features specific characteristics associated with bolts, such as a solid shank and a head for driving with a tool, allowing it to be easily tightened or loosened. The designation "M8" indicates its metric thread size, where "M" refers to the metric standard, and "8" indicates a diameter of 8 mm.

Bolts are typically used in conjunction with nuts and are designed to fasten multiple parts together by going through a pre-drilled hole, providing strong and reliable joins in structures or assemblies. The hex head allows for the use of a wrench or socket, making it easier to apply sufficient torque for secure fastening. This differentiates the M8 hex head bolt from other fasteners like screws, washers, or rivets, which have distinct functions and designs that do not apply in the same context as a bolt.