These slipper socks are knit using any needle size 8 to 11, depending on the weight of your yarn and the density of the fabric you wish to knit. Approximately 105 yards are needed, depending on the size sock you wish to knit. It is generally an adult size pattern. I knit them on 2 needles and sew a seam up the side. The socks in the picture I used several different yarns. The yarn that best matches the picture is November.