The herringbone stitch creates a double thick brim that looks fabulous!
The herringbone stitch has less stretch so be sure to measure your wearers head size.

The yardage shown is for a sock weight yarn held 2 together but 100g of either DK or Worsted weight yarn will work as well.

Gauge
Sorry for any confusion, the gauge in the pattern is for the straight stitch. The gauge for the Herringbone stitch using 6mm needles is 7 stitches per inch with Fingering held double, DK and Worsted weight yarn. Because each stitch is knit twice it is a very narrow stitch even on such large needles.

Found a great video for knitting Herringbone in the round.
https://www.youtube.com/watch?v=OFjM26RKliE