Socket Head Bolt
Button socket cap screws (also known as button head screw) have a low domed, wider bearing surface than standard socket heads. They provide a more finished appearance and are ideal when clamping material is too thin to countersink the screw. Button head caps can also be used in applications where a flush appearance is desired for either safety or aesthetic reasons.
These threaded fasteners have a raised hexagon drive that accepts an Allen wrench or hex key for installation and removal. They are used in a wide variety of industrial, mechanical and automotive applications. Button head bolts can be tightened to higher torque specifications than slotted or cross recessed drive machine screws.
Although they can be tightened with greater torque than other screw types, it is recommended that these screws and bolts be installed using a wrench in good condition. The lower contact area of the head with the driver will cause these screws to loosen more easily than other fastener types if the screw is tightened beyond the suggested torque value.
These metric button screws are typically made of 18-8 stainless steel and may be mildly magnetic. They have a tamper-resistant Torx drive, which prevents unwanted removal of the screw without the use of special tools. An o-ring under the head blocks leaks and seals out dirt and dust. Metric button socket cap screws are available in various lengths and diameters. Non-standard sizes and materials are available as a special order. Button Head Bolt