M4: This indicates the nominal diameter of the screw thread is 4 millimeters.
0.7: This represents the thread pitch, which is the distance between adjacent threads, measured in millimeters.
Fine Thread: In metric threads, a smaller pitch (like 0.7mm for M4) indicates a fine thread, while a larger pitch (like 0.7mm for M4) indicates a coarse thread.
Standard M4 Pitch: The standard or coarse thread pitch for M4 is 0.7mm.

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