M1.6 vs M2

They differ by 0.4 mm across the threads — enough that they are never interchangeable, but little enough that they are easy to mix up in a parts tray.

M1.6M2
Thread diameter1.60 mm2.00 mm
Standard pitch0.35 mm0.4 mm
Tap drill1.25 mm1.6 mm
Clearance hole1.8 mm2.4 mm
Cap head Ø3 mm3.8 mm
Hex key1.5 mm1.5 mm
Torque into steel12-20 N·cm25-40 N·cm
Into plastic6-10 N·cm12-20 N·cm

M1.6 is normally used for

Laptop hinges and boards, connectors, small standoffs, instrument panels

Everything M1.6 fits →

M2 is normally used for

Laptop bottom covers, SSD brackets, cameras, drones, small enclosures

Everything M2 fits →

If you are not sure which one you have

Measure across the outside of the threads with a caliper. A reading within about 0.1 mm of the nominal size is your answer — 1.6 mm means M1.6, 2.0 mm means M2.

Use the screw size finder →

Buy either size

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