The double cable up the back.
A close-up of the yarn and the stitch pattern that goes into these. They were inspired by "The Raven," and you can see at the top where it looks like raven wings? Yeah. Very cool. And it makes a neat sorta-scalloped edge to the socks.
This is the Lenore colorway, from October of the 2007 sock club, and it's part of Blue Moon's new series of Raven colorways. I *love* these socks.
