Square head bolts are fasteners with a specific head shape, usually used in connections that need to withstand high torque or tension. Common materials are carbon steel and stainless steel (SUS304, SUS201, SUS316...). Square head bolts come in a variety of sizes, and you can choose the appropriate diameter and length as needed. Common diameters range from M6 to M30, and lengths range from 10mm to several hundred millimeters. The thread types include full thread or partial thread, and the surface treatments include blackening and galvanizing. It plays an important role in many industries.