2. Versatility Hex head self-drilling screws are designed for use in a variety of materials, making them highly versatile. They are commonly used in metal roofing, siding, and other metal-to-metal applications, as well as in wood and plastic. Their ability to fasten dissimilar materials together makes them ideal for a wide range of projects, from residential to commercial construction.

Hex head self-drilling screws are characterized by their hexagonal head, which allows them to be driven using a wrench or a socket, providing an excellent grip and making them easy to install. What sets them apart is their unique ability to drill into materials without the need for pre-drilling, thanks to their sharp, self-tapping points. This feature not only saves time but also reduces the need for additional drilling equipment, making the installation process more efficient.

Another drawback is that T-head screws can be more expensive than standard screws due to their specialized design and manufacturing process. However, many engineers and manufacturers consider this cost justified given the benefits they provide in terms of connection strength and reliability.

5. Precast Elements M20 bolts are used to connect precast concrete elements during assembly, providing quick and effective ways to join large structures without extensive welding or other complex methods.