SIZE:1/4-20 x 2'' Specification: Thread Diameter 0.250" Head Diameter 0.437" Head Height 0.132" Screw Length 2 inch Package Included: 100 (+-2%) Button head socket cap screws are precision threaded fasteners with an internal socket drive (also called allen hex drive) for installing in areas with limited side clearance.The internal hex drive requires an Allen wrench. They are known for their effecient application performance and endurance widely used in a variety of industries such as construction, manufacturing, engineering, assembling, aircraft and so on and serves a wide range of use for professionals, amateurs, landlords, repairmen and DIYers. These screws are available with a variety of head shapes, which determine how the screw interacts with the mating surface, and drive styles, which determine the type of tool required to install the screw. The high quality 304 stainless steel provide perfect strength and good corrosion resistance in bad environments like high temperature, cold weather and high humidity areas without the need for time consuming and costly maintenance. Contact Us: If you have any questions when using, please feel free to contact us by Amazon message.