Sizes
There are four sizes in this pattern. The finished hat dimensions are 15.5 (18.25, 21, 23.5) in / 39.5 (46.5, 53, 60) cm Most people like their hats snug, so if that’s what you’re looking for, choose a finished hat size that is somewhat smaller than your actual head.)
Materials
You'll need 180 (210, 240, 270) yds/ 165 (193, 220, 247) m worsted weight yarn. I knit my sample in Hypothesis Yarn Worsted, colorway Royal, 100% Superwash Merino, 210 yds/115 g skein (192 m/ 3.53 oz).
One set of needles for small-circumference knitting (suggested size: US 8/5mm), plus one set of needles two sizes smaller (suggested size: US 6/4mm). You'll also need one stitch marker for the beginning of the round and a tapestry needle to weave in ends.
Needles and Tools