It's a Rii Mini Keyboard i4, and my concern is that it's a microphone. I just noticed the hole and think I'm probably wrong in what it is considering how big a deal it would be if it was a mic that isn't advertised.
What could this hole be for or what is it? Thanks in advance, hope this doesn't violate any rules.
Injection mold tooling is expensive ($40k+) and PCB iteration is cheap. Its especially hard to add holes to existing plastic parts as that requires adding material to the tool (as opposed to cutting material away). It's possible a past prototype or future version had/will have a microphone. Or they just wanted to keep their options open.
I do a of lot of sourcing for plastic injection mold tooling. $40k is a pretty high price for this one, but if you are getting out made in the US, then it's not completely unreasonable. Sourcing it from China would be considerably less than half that price.
Assuming they're buying extremely large quantities (likely over 10k), I'd guess that this part (top and bottom shells) cost about $3 to $5 for both, not including shipping costs.
Good to know! I'm an electrical engineer, and $40k was always the generic number we got tossed from the MEs. Not sure if it was for domestic or multi-part molds.
For reference, I'd wager single quantities PCB prototypes at around $100 each and maybe $5 at scale.