round head self drilling screw

A double end stud, as its name implies, is a type of fastener that features two threaded ends with a unthreaded shank in between. This unique configuration allows it to serve as a versatile connector in a range of applications. Historically, the design of the double end stud emerged from the need for robust fastening solutions that could withstand significant stress and load. Its origins can be traced back to the industrial revolution when the demand for durable and reliable construction materials surged as industries expanded.


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Butterfly screws, also known as wing nuts or butterfly nuts, are a distinctive type of fastener that have gained popularity in various engineering and design applications due to their unique shape and functionality. These screws derive their name from their appearance, which resembles a butterfly in flight when the wings are fully opened. The wings serve as handles, allowing for quick and easy tightening or loosening by hand without the need for additional tools.

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