Im trying to disassemble my computer and the chart below is from the manual.
I cannot find any specific M2x1.9, M2x2.5 and such screwdrivers online at any store. Please help.
"M2" is the type of screw and "x1.9" means "by 1.9(mm)" so it is an M2 sized screw that has 1.9mm of thread (the spiral section).
M2 specifies the "nominal" thread diameter as 2 millimeters. In practice the actual diameter is slightly smaller than 2mm as sharp tips of the thread are not a desirable feature and can cause mechanical problems.
What type of screwdriver you need depends entirely on what type of head the screw actually has. There are Pozi, Phillips and flat head types among others. At a quick glance a PZ0 (Pozi 0) is most likely "correct" for M2 Pozidrive screws, but you should figure out the specific type (Pozi or Philips) and use the correct bit.
You should just get a generic "precision" or "computer" screwdriver set. It will likely have most types of screwdriver in the most common sizes you will need and you can use the right screw head.
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