Black line on unibody (not screen)

[sainsburys]

Hi Guys,

so today I bought brand new mid 2012 MacBook Pro. Of course I examine almost every centimeter of unibody as well as OS X. There is one thing and I don't know what is for. I tried to google it but every answer is about black line on screen not unibody. So what for is this line? Is it some air ventilation?

 

[Silmarien]

edit: Its an IR receiver

 

[sainsburys]

Thanks.