Done another pair. This time with Paton's Kroy 4 ply sock yarn done toe up (Crazy Toes & Heels) with slipstitch heel on Addi 2.5mm circs. The cast off looks stretched out, but it really needs to be loose & when worn it just looks normal. The cast off was done with a crochet hook which adds an extra stitch. The ribbing is K3, P1. He has a very high arch so the best kind for him are the socks with a traditional heel flap & gusset.