●High quality: these screws are made of stainless steel with high hardness and are suitable for steel and metal working. ●Advantages: these self-tapping screws have sharp holes that do not require additional machining. ●Save time: you can drill, tap and lock at the same time. This ensures safety and saves time at work. ●Versatile: these self-drilling screws are mainly used for fixing steel tiles or for simple construction of thin panels. ●- - -