nominal size compared to gauge wire size?

[x91evo]

I am working with a harness with multiple smaller sized wires.
Need to convert the nominal size to gauge size for some harness connector pins.
I have no idea on what these letters or numbers mean
The three nominal sizes I am looking at are:

-AVSS 0.5
-AVSSH-1.25F
-AVSSHCS-0.5X2A

In order from smallest to largest.
I tried to make sense of the makers (sumitomo surprise) website, But I couldnt seem to figure it out.

Any input would be appreciated!

[Broke_Audio_Addict]

http://en.wikipedia.org/wiki/American_wire_gauge.

Scroll down to the table the numbers you have are the cross sectional area in mm squared. find your number in that column and then look at the gauge size to the left.