1. countersunk head screw, also known as flat machine screw and flat head screw, has a 90-degree cone at its head, similar to common wood screws. There are tool fastening grooves on the head, such as straight line, crosshair and hexagon socket. Screws play the role of connecting two or more objects, and are indispensable necessities in daily life or industrial manufacturing, including countersunk bolts (with grooves) and countersunk bolts (with tenons).

2. The head of the cross pan head screw is round, also called "". What is a cross? That is, the head of the screw is cruciform. The cross is made by fine stamping of the cross. The materials of Phillips pan head screws are divided into iron, namely carbon steel and stainless steel. There are three kinds of carbon steel, low carbon steel, medium carbon steel and high carbon steel. Stainless steel includes stainless steel SUS20 1 and stainless steel SUS304, stainless steel SUS3 16, stainless steel SUS404, etc. Cross pan head screw electroplating colors are. Common electroplating includes white nickel, black zinc and blue zinc. And environmental protection includes environmental protection white zinc, environmental protection colored zinc, environmental protection white nickel, environmental protection blue zinc and so on.