Gottlieb Royal Guard - what is this?

Yes I'm still learning. This is in the back where the score is kept and for the life of me don't have a clue what it does. Yes I have the schematics.
Please HELP.

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There it is, Thank you. When you get to be my age it's hard to see something when it's in front of your face.
Confusing though: Plug value plus socket value equals point score is pretty easy to understand but...the card shows the socket on the left side from top to bottom:
400, 300, 200, 100, 1000 and on the right side: 900, 800, 700, 600, 500

The plugs are: #0 = 0, #1 = 1000, #2 = 2000, #3 = 3000 up to #9 = 9000

That's the confusing part. Putting #2 plug which is 2000 into 800 socket should equal 2800 ??? I am at a loss...

I am such an idiot! THE REPLAY KNUCKLE HEAD! Wow thank you both. These are the numbers I set for a replay. I'm getting old.