Common Specifications Of Screws
A: Metric screw B: American screw C: Inch screw
A: Metric mechanical screws: Metric
Ex: M3 x 6 -- P P B: M3 mechanical screw, 6mm long, cross, round, flat head, black plated.
Finish Code: Appearance processing specifications
Head Code: the appearance of the Head.
Screw head shape. Cylinder head. Oval head. Countersunk head. Spherical cylindrical head. Pan head. Round head. Hex head.
Thread Code
Head groove, feature model
Length Code: Screw Length (mm)
A-1: Thread Code: screw model
Metric screws directly mark the screw type with the outer diameter of the screw.
Such as M3, that is, 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 behind the screw type, sometimes the screw pitch is indicated.
Such as M3x0. 5, M4x0. 70, M5x0. 8, M6x1.
But because of standard norms, it's usually not mentioned.
A-2: Length Code: Screw Length:
Metric screws, directly marking screw length, unit: mm.
The total length of the screw is only calculated below the head, not including the head height.
With the exception of flat head screws, the total screw length is marked with head height.
A-3: Drive Code/ head groove, features.
