Merinowoll Beanie Unisex Interlock for adults merino 280g/m2

Compared to traditional fiber merino wool is extremely fine and non-irritating. Has exceptional thermoregulation properties in winter and in summer, is a good flame retardant and carries a SPF 50.

And if you want to integrate it back into nature: burying it will completely degrade itself in 6-9 months where synthetics require even 30-40 years (!).