It has a cylindrical head with a hexagonal socket, to fit an Allen key. It is used in applications where there is not enough space available for a standard socket head cap screw. Its field of application is in heavy engineering, dies and tools, plastic injection molds, pumps in internal and external applications, automotive and naval industry, military equipment, automation, security fixings, high temperature applications, etc. This type of screw is mostly applied to places that are difficult to access for other types of screws.