Has a similar thread design as a socket cap screw. The dome-shaped head is wider and has a lower profile than a socket cap screw. Used when a wider bearing surface or a smoother, more finished appearance is desired. Button head cap screws do not afford the strength of socket head cap screws and are designed for light fastening applications. They are not recommended for critical, high strength applications. Button socket cap screws offer a wider bearing surface and high tensile strength but are still low profile like other socket cap screws