I laugh every time I see this on my FishFinder.  I am venturing into the ocean, but I have the habit of blasting the contact points with Electronic cleaner spray, so I am not worried about corrosion.  

 

what a dork!  hahah..

 

I never contacted Garmin for a replacement contact cover.  

 

 

The pic.  Come on!   Details matter.  literally square peg, round hole.  hahah

 

That rectangular rubber cover is meant to cover the pins on the other side of the cradle when removing the MFD from the cradle.

Really?  Where?

There is a release lever (about 3" long black piece) on the top of the unit. Left hand side of your picture. The Cover fits the connections under the unit.  It's so you can remove the head from the cradle. 

FM

The cradle is meant to stay on the boat and the power meant to stay hooked up so there’s no need for a cover for the port. The screen can be removed and rectangular cover goes over the connections on the front. That’s why it appears like square peg round hole.

admittedly, I feel kinda dumb (face red).  

9 hours ago, Darth-Baiter said:

admittedly, I feel kinda dumb (face red).  

We learn something new everyday.