Hello Chris Ruegsegger,
As you have guessed, the skin is a custom one - however, it's unlike the other Menu skins; furthermore, the "chevron" button on the site uses a context menu rather than a submenu. You can find the skin for the root menu group attached to this post - please note that it uses images for all its text items.
If you need a more functional skin, let us know - we will consider converting it to a fully functional skin.
All the best,
the Telerik team
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