Common knowledge of small screws

Small screw type

When you don't expect the head to hang, you probably want to take the hook component normally. It is necessary to use the tapered processing (※ countersunk processing) in the support of the flat head screw.	The most frequently used model screw. The thick head allows it to securely engage the drive and be able to tighten firmly.	The head has a large shape, which can add combat accumulation, and the screws with other shapes can be compared to the expected locking results. In addition, since it looks beautiful, it is also used as decoration screws.	The head is slightly larger than the head, and there is a soft round shape and a flat seat on the top. It is used for flat metal accessories engraved with flowing and not sitting.

For the length of the small screw

Screws have different length standards, depending on the shape of the head.
Careful screws refer to the length from the top of the screw to the top
, Flat-head screws and truss screws refer to the length from below the screw neck to the screw tip.

Small screw size representation

Small screw standard

Nominal diameter	Board\/Circle Board		pot		truss		Binding
	Head diameter	Head high	Head diameter	Head high	Head diameter	Head high	Head diameter	Head high
M2	4	1.2	3.5	1.3	4.5	1.2	4.3	1.2
M2.3	4.6	1.35	4	1.5	5.2	1.4	4.9	1.4
M2.5	5	1.45	4.5	1.7	5.7	1.5	5.3	1.5
M2.6	5.2	1.5	4.5	1.7	5.9	1.6	5.5	1.6
M3	6	1.75	5.5	2	6.9	1.9	6.3	1.9
M 3.5	7	2	6	2.3	8.1	2.2	7.3	2.2
M4	8	2.3	7	2.6	9.4	2.5	8.3	2.5
M5	10	2.8	9	3.3	11.8	3.1	10.3	3.1
M6	12	3.4	10.5	3.9	14	3.7	12.4	3.7
M8	16	4.4	14	5.2	17.8	4.8	16.4	4.8
M10	20	5.7	19	6	21	5.1	-	-
M12	24	6.7	-	-	-	-	-	-

• (Root source: China Standard Parts Network)