Ph 1: The diameter of screwdriver head is about 5.0mm, which is used for cutting M2-M3 screws;
Ph2: The diameter of screwdriver head is about 6.5mm, which is used for M3.5-M5 screws;
Ph3: The diameter of screwdriver head is about 8mm (used for extra-large cross screws).
A screwdriver is a common tool for turning a screw into place. It usually has a thin wedge-shaped head that can be inserted into the groove or notch of the screw head.
The dialects in Beijing, Tianjin, Hebei, Shanxi, northern Shaanxi and northern Henan are called "screwdriver", while those in northern Henan are more commonly known as "screwdriver", those in Jiangxi, Anhui, Hubei, south of the Yellow River in Henan, Guanzhong in Shaanxi, and those in the central and western regions are called "screwdriver".
There are two main types: the word (minus sign) and the cross (plus sign). There are also common hexagonal screwdrivers, including hexagon socket and external hexagon.