From website:

NL11 - FELTED HELMET HAT

The hat starts with the earflaps, is knit circular for the main body and finishes with a rounded top. The felting process is same as for the other patterns.

SIZES: Child (women, men)

YARNS: Worsted weight, 100 gm of 100 % non - washable wool.

NEEDLES: 16”circular #10