Any weight, fiber or textured yarn may be used for this hat. Using the simple formula, create a hat that fits. Nine different styles possible.

From website:

NL23 - MORE HATS THAT FIT

Using the formulas and any yarn knit a hat that fits. Choose a single layer band, earflaps or a fold up cuff for the beginning and finish off with a choice of flat, square or full top. This adds up to nine hat styles same as in HATS THAT FIT.

SIZE: To fit any head size

YARN: Any weight of your choice

NEEDLES: Circular needles appropriate for yarn weight

See also NL5 Hats That Fit