A: Metric Screw B: American Standard Screw C: British Standard Screw

A: 公制机械螺丝: Metric

Example: M3 x 6 – P P B: M3 mechanical screw, 6mm long, cross, round flat head, black plated.

Finish Code: Appearance Processing Specification

Head Code: Head shape.

Screw head shape. Cylindrical head. Semi-flush head. Flush head. Spherical cylindrical head. Pan head. Half-round head. Hexagonal head.

Thread Code

Screw Model: Drive Code, Head Slotted, Feature Model

Length Code: Screw Length (mm)

A-1: Thread Code: Screw Model

Metric screws are directly indicated by the screw outer diameter for the screw model.

If M3 means the screw diameter is 3.00mm, then M4 means the screw diameter is 4.00mm.

公制螺纹规格 x 螺距:

Note: Metric screws are sometimes followed by the screw pitch indicated after the screw model number.

Such as M3x0.5, M4x0.70, M5x0.8, M6x1.

But because of the standards, it is usually not mentioned.

A-2: Length Code: Screw Length:

Metric screw, directly indicates the screw length, with units in mm.

The total length of the screw is indicated, only the length below the head is calculated, excluding the height of the head.

However, the total length of the flat head screw is indicated to include the height of the head.

A-3: Drive Code / Head Slot, Feature.

A: 公制螺丝 B: 美制螺丝 C: 英制螺丝

A: 机械螺丝：公制

Example: M3 x 6 -- P P B: M3 mechanical screws, 6mm long, cross, round flat head, plated black.

Finish Code: Appearance processing specification

Head Code: head appearance.

Screw head shape. Cylindrical head. Half sunk head. Heavy head. Spherical cylindrical head. Do your head up. Half round head. Hexagonal head.

Thread Code

Drive Code: Head trench, feature model

Length Code: Screw length (mm)

A-1: Thread Code: Screw type

For metric screws, the screw type is directly marked with the outside diameter of the screw.

For example, M3 indicates that the outer diameter of the screw is 3.00mm. M4 means the outer diameter of the screw is 4.00mm.

公制螺纹规格 x 螺距:

Note: Metric screws are placed behind the screw type, sometimes the screw spacing is indicated.

Such as M3x0. 5, M4x0. 70, M5x0. 8, M6x1.

However, due to the standard rules, it's usually not mentioned.

A-2: 长度代码: 螺钉长度:

Metric screws, directly marking screw length in mm.

The total length of screws is indicated by counting the length below the head only, excluding the head height.

Except for flat head screws, the total length of the screws is indicated by the head height.

A-3: 驱动代码/头部沟槽，特征。