Understanding the screw sizes required for disassembling Lenovo Z510

[Smartflight]

I have a Lenovo Z510 bought several years ago. I finally decided to order a new RAM module to install.

I found this guide on Lenovo's website. The screw sizes I need to unscrew/screw are:

• 
  * M2 x 2.5mm (flat head, nylok coated)
  * M2 x 4.9mm (flat head, nylok coated)
  * M2.5 x 6mm (flat head, nylok coated)

I need to go out and buy screwdrivers for these sizes. What I am not able to understand is what the "M2" and "M2.5" are. It is unlikely the store in my locality would know about it either, so I would be tasked with simplifying it for him. How would I go about doing that?

 

[USAFRet]

You just need a set of jewelers screwdrivers. Generally in a set of 6 or more.

 

[mbarnes86]

Hi

M2 & M2.5 are the diameter of the screws (metric in mm)
'nylok coated' coated in a plastic film designed to prevent the screw undooing under vibration

nothing there tells you what type of screw driver is needed

could be X or -- shaped have a look first or take the laptop with you

you will see lots of suitable tool sets on Ebay & Amazon

regards
Mike Barnes