Hex socket screws, often used in mechanical, basically have facilitating fastening, disassembly, not easy to slide Angle and other advantages. Hex socket wrench is usually a 90 ° turns, bend at the end of long side short, with a short side dozen screw, hand long side can save a lot of force and better able to tighten the screws. Long at one end points round head (hexagonal cylindrical similar sphere) peace head, round head can easily disassembled, installing inclined into some inconvenience next wrench sites. Hex manufacturing costs than hex low more, its advantages and screw head (wrench stress position) than hex thin, some local not hex can replace. Besides cost low, the dynamic intensity is small, low mechanical accuracy requirements of the Hex socket screws than hex much less.