A: 公制螺丝B: 美规螺丝 C: 英制螺丝

A: 公制机械螺丝: Metric

Ex: M3 x 6 – P P B : M3 机械螺丝，6mm 长，十字，圆扁头，镀黑.

Finish Code:外观处理规格

Head Code: 头部外型。

螺丝头部外形。圆柱头。半沉头。沉头。球面圆柱头。盘头。半圆头。六角头。

Thread Code

螺丝型号 Drive Code: 头部剖沟，特征型号

Length Code: 螺丝长度 (mm)

A-1: Thread Code: 螺丝型号

公制螺丝直接以螺丝外径标示螺丝型号，

如M3 即螺丝外径为3.00mm.; M4 即螺丝外径为4.00mm.

Metric Thread Size x Pitch:

Note: 公制螺丝于螺丝型号后方，有时会注明螺丝牙距.

如M3x0.5,M4x0.70,M5x0.8,M6x1.

但因为标准规范，通常不提.

A-2: Length Code: 螺丝长度:

公制螺丝，直接标示螺丝长度，单位为mm.

螺丝之总长度标示，只计算头部以下之长度，不含头部高度.

但平头螺丝例外，其螺丝之总长度标示含头部高度.

A-3: Drive Code/ 头部剖沟，特征.

A: Metric screws B: American screws C: British screws

A: Mechanical screws: Metric

Ex: 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.

Such as M3, the outer diameter of the screw is 3.00mm. M4 means the outer diameter of the screw is 4.00mm.

Metric Thread Size x Pitch:

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

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

But because of the standard rules, it's usually not mentioned.

A-2: Length Code: Screw length:

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.

With the exception of flat head screws, the total length of screws is indicated with head height.

A-3: Drive Code/ head trench, features.