plastic expansion screw

While not fasteners in the traditional sense, washers are often used in conjunction with bolts, nuts, and screws to improve their performance. Washers distribute the load of the fastener over a larger surface area, helping to prevent damage to the material being fastened and reducing the risk of loosening due to vibration. There are several types of washers, including flat washers, lock washers, and fender washers, each serving specific functions in various applications.


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The 'head' of the bolt refers to its top part that sits above the threaded shaft. It's the part that provides the gripping surface for the tool used in installation or removal. The hexagonal shape offers several advantages over other head designs. Firstly, it allows for better torque application, enabling precise tightening without slipping. Secondly, the six-sided profile can accommodate larger wrenches or sockets, which can generate more torque, ideal for heavy-duty applications.

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