From the Knit Picks Website:
This is a pattern for socks and a scarf that have bundled together because of their similar motifs. The scarf is a double-knit pattern. Both patterns are written for one circular needle (Magic Loop) and very brief instructions for the scarf knitted as a tube are also included. The socks are for three general widths with the only difference being the size of needle, weight of yarn and small difference in the heel for the largest size. Socks and scarf have separate charts. Links to videos are included for some of the more unusual techniques.

Needles:
Size 2.5 (3mm): long circular needle for Magic Loop (for scarf)

See also Scare Isle Scarf and Sox (Socks)