I am using Encore Yarn, which is 75% acrylic and 25% wool. The free pattern is from the Cascade website http://www.cascadeyarns.com/patternsFree/W104_220.pdf.
I used a size 7 needle. It features an afterthought heel, which I have never done before. While I was picking out the stitches I was thinking that this is way too hard to do. But then once I got them on the needles, I realized I liked it. This was SO much fun to make!