Why do some HP calculators have springs inside?

[lvt]

(12-26-2022 01:27 AM)rprosperi Wrote:  It should be no surprise that a calculator made in 2021 had no metal plate on the inner rear cover to act as an EMI shield. In fact finding any metal at all in the case assemblies today is likely driven more by cosmetic choices than shielding strategies.

So if I understand well, because my 12C has a metal "cheat sheet" on the ouside of the back and with the front metal plate they already form a sort of shield, those springs aren't needed, right?