2004 Tacoma driver side inner fender well

I have a 2004 Tacoma double cab Trd off road pre runner driver side front inner fender well what is missing in this spot exactly? Down in picture with arrow pointed to it and where could I find

 

To note there is really nothing there to protect just curious if anybody else could post a picture of there’s so I could reference

 

This is where the vac canister/tank for the 4WD actuator would be for the diff. On a PreRunner, it would be a blank of course. I don't believe it had a plastic cover/enclosure like the washer bottle (on the passenger side).

 

Great to know sir yes passenger side does have black hard plastic cover over washer bottle. And yea makes sense why they wouldn’t cap it there’s really nothing there