Extended Size is something I wished I had known about years ago. My shoe size is 9.5 to 10, which is what normal socks say they fit, but rarely fit comfortably. These socks are very comfortable. I have nerve damage in one leg, so finding socks that aren't too tight around the top is really important to me. These socks fit like a dream - they stay up but don't pinch or bind. Love that I can find fun socks that fit comfortably! (Thanks Joy of Socks!) Everyone needs a little pizzazz, and putting on a pair of fun socks is a great way to put a smile on your face in the morning.