I wondered one night if I could make a hat with both cables and shells, and so I did!

Finished Size
Size small: 20” circumference by 8” height
Size large: 22” circumference by 7.5” height

Gauge
Size small: 16 stitches = 4”; 8 rows = 4”; first three rounds of hat should equal 3” diameter
Size large: 14 stitches = 4”; 7 rows = 3.75”; first three rounds of hat should equal 3.5” diameter

Hook Size
Size small: US D (3.25mm)
Size large: US G (4.0mm)

Yarn
Size small: Patons North America Classic Wool Worsted, colorway 224: Grey Mix, 1 skein (actual yardage: 136.5 yards /124.8 meters, 65 grams)
Size large: Cascade Yarns® Venezia Worsted, colorway 103, 1 skein (actual yardage: 141.7 yards /129.6 meters, 65 grams)