They're perfect for wearing under a helmet as well as my hardhat even during the coldest winter days

I use it in cold winters,completely saved me from the cold, didn't bother the earphones - it even kept them tight in my ears

I've used this for unpredictable WI winters.

This is thin and sleek but really helps under bike helmets for winter/cold weather biking.

I needed a replacement for a fleece beanie that I wear under my helmet for bike commuting in the brutal Southern California winters

This beenie has solved several problems for me this winter while riding