This is an 8-stitch repeat based on a Barbara G. Walker lace pattern, Snowflake Eyelet, in “A Second Treasury of Knitting Patterns,” which has been modified for knitting in the round.

To increase or decrease the circumference of the cowl, add or subtract stitches in 8-stitch increments. For a narrower cowl, the pattern may be ended after row 6 or row 12.

I actually used 357 yds of Duet to knit this, and it is a heavy DK weight - you could also get away with using worsted weight yarn. The estimate of 375 - 500 yards should be more than ample, no matter your particular gauge.