Could anyone tell me what the strange plug is for located down and to the right of rear gate latch? It is round but has a square hole in the middle,I thought it was a drain of some description but does not appear to be that! I want to paint it but am apprehensive not knowing what it is for?
Help,anyone?

 

Is it exposed ONLY when the hatch is open? Facing towards the rear? And made of steel? If so, that sounds like the fitting where you stick the jack handle into to crank down the spare tire.

 

Thankyou really appreciate that.