[help] What is the property of this item?

Hope my title is close to what I'm discribing, sorry Mods.

In the image below I am trying to make this gripper, the seperator in the windows explorer that divides the file menus??

I've made about every gripper and half a dozen other things all invisible but I still can't figure out what in the heck value this?

I'm using stylebuilder? Any ideas? Or am I not making sense?

#218483

Go to the "XP Colors" section on the left side

Change the value for "Toolbar Edge Shadow" to match the color used on "Toolbar Background.bmp"

edit: there is probably a corresponding highlight color to change, but unfortunately I don't remember it. You'll just have to test some of the other colors in XP and/or "Classic Colors"

#218507