Question What is Lenovo laptop memory module mylar for

[think2]

We wanted to add some Ram to a Lenovo Thinkbook 16P Gen 2 laptop. The hardware manual described removing a mylar that was sitting over the RAM area - it says the mylar is not reusable and it didn't seem to serve any purpose so we didn't try to stick it back on after fitting the new RAM. Does anyone know what this mylar is for?
The laptop came with 8GB soldered in RAM and 8GB RAM in a socket so we swapped the 8GB for 16GB and now have 24GB total but it is annoying that it didn't come with 16GB of soldered RAM so we could have total 32 GB RAM instead of 24GB.

https://download.lenovo.com/consumer/mobiles_pub/lenovo_thinkbook_16p_gen2_en_hmm.pdf

 

[mikeymikec]

A quick google suggests that it's for electrical insulation. My guess in addition to that is that it's to shield the module against electromagnetic radiation. In my experience this stuff just lifts up (it adheres a little) and I press it back down when I'm done.