Self tapping screw is a type of screw with a drill bit, which is constructed using specialized electric tools to drill, tap, fix, and lock in one go. Self tapping screws are mainly used for the connection and fixation of thinner plates, such as the connection between color steel plates, the connection between color steel plates and purlins, wall beams, etc. Their penetration ability generally does not exceed 6mm, and the maximum is not more than 12mm. Self tapping screws are often exposed outdoors and have strong corrosion resistance.