I made this originally for drying and blocking knit hats that I make. It also works really well for drying any beanie after laundering.

This form allows airflow through the hat which allows for much faster drying; especially with a fan blowing on it.

The models pictured were printed with no supports. The underside of the “domed” part of the print doesn't print as well, but once cleaned up is not noticeable and does not hurt the functionality or the top finish. Supports will add significantly to the print time, and will make it look nicer, but honestly it works fine without.

The models are named by size (circumference x height in inches).

The pictured forms are 19x11 (black multicolored beanie) and 21x9 (white beanie)

Examples were printed at 0.3mm height with 0.6mm nozzle in PLA. There's no reason it shouldn't work with a smaller nozzle and layer height. I would suggest 0.3 layer height or lower.