Just found this in the centre cubby under the arm rest. Only had the car three years but in my defence I dont drive it much.

Any ideas what it is?

It to let air in to the jumbo box from the AC system 😉

 

If I remember correctly, you can either heat or cool it.

"Jumbo box" thats a laugh you'd be lucky to get a can of pop in there!

I remembering asking the same question some while back - I'd had my Yeti about 18 months when I discovered it and that was driving every day! 

..had mine for almost 3 years and never noticed that.. :)

Look in the glovebox and you should find the same thing there too 

I thought it was only found on Yeti's fitted with the factory sunroof.  Doesn't it open the plug to drain the footwells?