2mm Scuba Diving Hood Thermal Neoprene Wetsuit Hat Cap with Chin Strap Adjustable Diving Cap Swimming Cap Surfing Thermal Hood Beanie Headgear for Snorkeling Kayaking Sailing Canoeing Water Sports

I got this one because it seemed like it would cover more of my head and hair in the back to the base of my skull. It's fine though, and Jesus blesses you because he's God so it's all good!

Stretched out in one week

I wear this to keep my head and ears covered and warm while I’m in our heated swim spa here in the Pennsylvania Tundra, during freezing winter temps. It’s not a bathing cap- your hair will get a little damp, depending on how much water it’s exposed to. What you won’t feel is cold. It blocks wind and, any moisture that gets in, is instantly warmed up by the heat emanating from my head. No question I look a little goofy in it, what with my middle aged chubby cheeks, but I’m out there alone and to me, the most important detail is that my head and ears are protected. My hair is in a ponytail when I wear it, and it fits great.

This fits to your head very well because of the thin material, but that lack of thickness is crucial because it doesn't hold heat well at all. I seriously doubt the claim that it's 2mm thick, I would say it's more like 1mm. I have the Body Glove 3mm Super Beanie, and that is much thicker and warmer, although because of the thickness it doesn't quite "hug" or conform to your head shape as well, however it's quite a bit warmer than this one simply because of the thicker, stronger neoprene material. These are not worthless, but not all that effective in cold water surfing conditions like in Santa Cruz, California. Too stretchy also, effectively making the chin strap too long.